Account for removing existing collections first

src/api/core/ciphers.rs

@@ -783,6 +783,10 @@ async fn post_bulk_collections(
             err!("Cipher is not write accessible")
         }
 
+        // If the request is for mass adding collections, we need remove the cipher from all collections first.
+        if (!data.remove_collections) {
+            CollectionCipher::delete_all_by_cipher(&cipher.uuid, &mut conn).await?;
+        }
         for collection in &data.collection_ids {
             match Collection::find_by_uuid_and_org(collection, &data.organization_id, &mut conn).await {
                 None => err!("Invalid collection ID provided"),