- Replaced a single jQuery AJAX instance with our fetch wrapper
- Tested the issue branch reference selection and it works as before
# Demo using `fetch` instead of jQuery AJAX
![demo](https://github.com/go-gitea/gitea/assets/20454870/7e195632-41f8-494b-b599-f6291860f330)
Signed-off-by: Yarden Shoham <git@yardenshoham.com>
(cherry picked from commit 75a9f61f89caada64f6398130844281e4f088a73)