Original Gitea's repository no longer contains "Environment to INI" document referenced in "Managing Deployments With Environment Variables" section.
This commit fixes the reference by pointing the link to the last commit where needed doc was still present.
Reviewed-on: https://gitea.com/gitea/docs/pulls/315
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: andriibratanin <andriibratanin@noreply.gitea.com>
Co-committed-by: andriibratanin <andriibratanin@noreply.gitea.com>
