Gogs user can update repository content with read-only permission

Gogs is an open source self-hosted Git service. In version 0.13.3 and prior, the endpoint "PUT /repos/:owner/:repo/contents/*" does not require write permissions and allows access with read permission only via repoAssignment(). After passing the permission check, PutContents() invokes UpdateRepoFile(), which results in commit creation and the execution of git push. As a result, a token with read-only permission can be used to modify repository contents. This issue has been patched in versions 0.13.4 and 0.14.0+dev.