UI error when viewing a commit (clicking the down arrow)

[lunny]

https://try.gitea.io/ChristopherHX/actions-on-gitea/commit/eea6f360d405f8462ff2eb409b4362a049033efc

There is another bug, also record here:

Clicking the down arrow beside the number "10" of the filename triggers another error:

Originally posted by @wxiaoguang in #17443 (comment)

[wxiaoguang]

This bug is introduced by #16829 , will propose a PR to fix