refactor: add show button is not a primary action

src/components/shows/AddShowButton.vue

@@ -2,14 +2,14 @@
   <div v-if="isSuperuser">
     <AddShowModal v-if="!modal" ref="addShowModal" />
 
-    <b-button
-      variant="primary"
+    <button
+      type="button"
       data-testid="show-selector:add-show"
-      class="md:tw-whitespace-nowrap"
+      class="btn btn-default md:tw-whitespace-nowrap"
       @click="resolvedModal.openModal()"
     >
       {{ t('showCreator.title') }}
-    </b-button>
+    </button>
   </div>
 </template>