d5856fece7
Backport #21358 `SessionUser` should be protected against passing `sess` = `nil` to avoid ``` PANIC: runtime error: invalid memory address or nil pointer dereference ``` in https://github.com/go-gitea/gitea/pull/18452/files#diff-a215b82aadeb8b4c4632fcf31215dd421f804eb1c0137ec6721b980136e4442aR69 after upgrade from gitea v1.16 to v1.17. Related: https://github.com/go-gitea/gitea/pull/18452