* Fix verification of subkeys of default gpg key

Fix #10309

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Remove debug log

* Update models/gpg_key.go

* As per @6543

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

* Fix the intermittent TestGPGGit failures

Reattempt to open the listener if the port is busy with a delay up to a second
Switch from generating a private key each time, just use a known good key