We update gitea to v1.16.5 and update to using the golang:1.18-bullseye
image as the release notes [0] for this version indicate that upstream
has switched to golang 1.18 to build now.
I don't see any deltas in the templates that we updated between v1.16.4
and v1.16.5
[0] https://raw.githubusercontent.com/go-gitea/gitea/v1.16.5/CHANGELOG.md
Change-Id: I794d0db2dbb64d962debaba385eb0e46b463877a