Change mysql database collate to utf8mb4, fix #9030
This commit should fix #9030 (closed), which allows to insert and update strings that contain emoji or other special unicode characters in mysql schema.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
This commit should fix #9030 (closed), which allows to insert and update strings that contain emoji or other special unicode characters in mysql schema.