Fixes https://github.com/go-gitea/gitea/issues/30005. Regression from
https://github.com/go-gitea/gitea/pull/29945.
There was only once instance of `tw-content-center` before that PR, so I
just ran below command and reverted that one instance.
```sh
perl -p -i -e 's#tw-content-center#tw-items-center#g' web_src/js/**/* templates/**/* models/**/* tests/**/*
```
This is the implementation of Recent Commits page. This feature was
mentioned on #18262.
It adds another tab to Activity page called Recent Commits. Recent
Commits tab shows number of commits since last year for the repository.