feat: accept date string and objects for getISODateString and getTimeString

src/utilities.js

+import { ensureDate } from '@/util'
+
 export function uppercaseFirst(string = '') {
   return string.charAt(0).toUpperCase() + string.slice(1)
 }
@@ -15,7 +17,7 @@ export function has(obj, prop) {
 }
 
 export function getISODateString(date) {
-  date = date ? date : new Date()
+  date = date ? ensureDate(date) : new Date()
   const year = date.getFullYear()
   const month = (date.getMonth() + 1).toString().padStart(2, '0')
   const day = date.getDate().toString().padStart(2, '0')
@@ -23,7 +25,7 @@ export function getISODateString(date) {
 }
 
 export function getTimeString(date, withSeconds = false) {
-  date = date ? date : new Date()
+  date = date ? ensureDate(date) : new Date()
   const hours = date.getHours().toString().padStart(2, '0')
   const minutes = date.getMinutes().toString().padStart(2, '0')
   const seconds = date.getSeconds().toString().padStart(2, '0')