Enable more revive linter rules (#30608)

Noteable additions:

- `redefines-builtin-id` forbid variable names that shadow go builtins
- `empty-lines` remove unnecessary empty lines that `gofumpt` does not
remove for some reason
- `superfluous-else` eliminate more superfluous `else` branches

Rules are also sorted alphabetically and I cleaned up various parts of
`.golangci.yml`.

(cherry picked from commit 74f0c84fa4245a20ce6fb87dac1faf2aeeded2a2)

Conflicts:
	.golangci.yml
	apply the linter recommendations to Forgejo code as well

services/auth/source/ldap/source_sync.go

@@ -159,7 +159,6 @@ func (source *Source) Sync(ctx context.Context, updateExisting bool) error {
 				!strings.EqualFold(usr.Email, su.Mail) ||
 				usr.FullName != fullName ||
 				!usr.IsActive {
-
 				log.Trace("SyncExternalUsers[%s]: Updating user %s", source.authSource.Name, usr.Name)
 
 				opts := &user_service.UpdateOptions{