Prepend commit message to template content (#20429)
Prepend commit message to template content (#20429)

- When a repository has a pull request template, it will always override
the current content. With this PR it will prepend content to the
template content when appropriate. This is similar how GitHub(and GitLab
I presume) does it and it saves developers time to not go open their
commit and copy paste their will written commit message.


go-gitea/gitea,go-gitea/gitea,go-gitea/gitea