add .gpg url (match github behaviour) (#6610)

* add .gpg url (match github behaviour)

* wildcard

* test to export maximum data

* working POC

* add comment for old imported keys

* cleaning

* Update routers/user/profile.go

Co-Authored-By: sapk <sapk@users.noreply.github.com>

* add migration script

* add integration tests

models/user.go

@@ -747,7 +747,7 @@ var (
 		".",
 		"..",
 	}
-	reservedUserPatterns = []string{"*.keys"}
+	reservedUserPatterns = []string{"*.keys", "*.gpg"}
 )
 
 // isUsableName checks if name is reserved or pattern of name is not allowed