Revert "Make CharFields and TextFields not nullable"

This reverts commit 1546a2c2.

program/migrations/0055_auto_20230418_2218.py

-# Generated by Django 3.2.18 on 2023-04-18 20:18
-
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-    dependencies = [
-        ("program", "0054_alter_schedule_last_date"),
-    ]
-
-    operations = [
-        migrations.AlterField(
-            model_name="host",
-            name="updated_by",
-            field=models.CharField(blank=True, default="", max_length=150),
-        ),
-        migrations.AlterField(
-            model_name="note",
-            name="updated_by",
-            field=models.CharField(blank=True, default="", max_length=150),
-        ),
-        migrations.AlterField(
-            model_name="show",
-            name="updated_by",
-            field=models.CharField(blank=True, default="", max_length=150),
-        ),
-        migrations.AlterField(
-            model_name="userprofile",
-            name="updated_by",
-            field=models.CharField(blank=True, default="", max_length=150),
-        ),
-    ]

program/migrations/0056_auto_20230418_2229.py

-# Generated by Django 3.2.18 on 2023-04-18 20:29
-
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-    dependencies = [
-        ("program", "0055_auto_20230418_2218"),
-    ]
-
-    operations = [
-        migrations.AlterField(
-            model_name="category",
-            name="subtitle",
-            field=models.TextField(blank=True, default=""),
-        ),
-        migrations.AlterField(
-            model_name="host",
-            name="biography",
-            field=models.TextField(blank=True, default=""),
-        ),
-        migrations.AlterField(
-            model_name="note",
-            name="playlist",
-            field=models.TextField(blank=True, default=""),
-        ),
-        migrations.AlterField(
-            model_name="note",
-            name="tags",
-            field=models.TextField(blank=True, default=""),
-        ),
-        migrations.AlterField(
-            model_name="show",
-            name="description",
-            field=models.TextField(blank=True, default=""),
-        ),
-        migrations.AlterField(
-            model_name="show",
-            name="internal_note",
-            field=models.TextField(blank=True, default=""),
-        ),
-    ]

program/migrations/0057_alter_category_subtitle.py

-# Generated by Django 3.2.18 on 2023-04-18 20:39
-
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-    dependencies = [
-        ("program", "0056_auto_20230418_2229"),
-    ]
-
-    operations = [
-        migrations.AlterField(
-            model_name="category",
-            name="subtitle",
-            field=models.CharField(blank=True, default="", max_length=32),
-        ),
-    ]

program/models.py

@@ -54,7 +54,7 @@ class Category(models.Model):
     is_active = models.BooleanField(default=True)
     name = models.CharField(max_length=32)
     slug = models.SlugField(max_length=32, unique=True)
-    subtitle = models.CharField(blank=True, default="", max_length=32)
+    subtitle = models.TextField(blank=True, null=True)
 
     class Meta:
         ordering = ("name",)
@@ -144,7 +144,7 @@ class Image(models.Model):
 
 
 class Host(models.Model):
-    biography = models.TextField(blank=True, default="")
+    biography = models.TextField(blank=True, null=True)
     created_at = models.DateTimeField(auto_now_add=True)
     created_by = models.CharField(max_length=150)
     email = models.EmailField(blank=True)
@@ -152,7 +152,7 @@ class Host(models.Model):
     is_active = models.BooleanField(default=True)
     name = models.CharField(max_length=128)
     updated_at = models.DateTimeField(auto_now=True, blank=True, null=True)
-    updated_by = models.CharField(blank=True, default="", max_length=150)
+    updated_by = models.CharField(blank=True, max_length=150, null=True)
 
     class Meta:
         ordering = ("name",)
@@ -204,7 +204,7 @@ class Show(models.Model):
     created_at = models.DateTimeField(auto_now_add=True)
     created_by = models.CharField(max_length=150)
     default_playlist_id = models.IntegerField(blank=True, null=True)
-    description = models.TextField(blank=True, default="")
+    description = models.TextField(blank=True, null=True)
     email = models.EmailField(blank=True, null=True)
     funding_category = models.ForeignKey(
         FundingCategory,
@@ -215,7 +215,7 @@ class Show(models.Model):
     )
     hosts = models.ManyToManyField(Host, blank=True, related_name="shows")
     image = models.ForeignKey(Image, null=True, on_delete=models.CASCADE, related_name="shows")
-    internal_note = models.TextField(blank=True, default="")
+    internal_note = models.TextField(blank=True, null=True)
     is_active = models.BooleanField(default=True)
     is_public = models.BooleanField(default=False)
     language = models.ManyToManyField(Language, blank=True, related_name="shows")
@@ -244,7 +244,7 @@ class Show(models.Model):
         Type, blank=True, null=True, on_delete=models.CASCADE, related_name="shows"
     )
     updated_at = models.DateTimeField(auto_now=True, blank=True, null=True)
-    updated_by = models.CharField(blank=True, default="", max_length=150)
+    updated_by = models.CharField(blank=True, max_length=150, null=True)
 
     class Meta:
         ordering = ("slug",)
@@ -467,14 +467,14 @@ class Note(models.Model):
         related_name="notes",
         default=1,
     )
-    playlist = models.TextField(blank=True, default="")
+    playlist = models.TextField(blank=True, null=True)
     slug = models.SlugField(max_length=32, unique=True)
     summary = models.TextField(blank=True)
-    tags = models.TextField(blank=True, default="")
+    tags = models.TextField(blank=True, null=True)
     timeslot = models.OneToOneField(TimeSlot, on_delete=models.CASCADE, unique=True)
     title = models.CharField(max_length=128)
     updated_at = models.DateTimeField(auto_now=True, blank=True, null=True)
-    updated_by = models.CharField(blank=True, default="", max_length=150)
+    updated_by = models.CharField(blank=True, max_length=150, null=True)
 
     class Meta:
         ordering = ("timeslot",)
@@ -500,7 +500,7 @@ class UserProfile(models.Model):
     created_at = models.DateTimeField(auto_now_add=True)
     created_by = models.CharField(max_length=150)
     updated_at = models.DateTimeField(auto_now=True, blank=True, null=True)
-    updated_by = models.CharField(blank=True, default="", max_length=150)
+    updated_by = models.CharField(blank=True, max_length=150, null=True)
     user = models.OneToOneField(
         User,
         on_delete=models.CASCADE,