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

modules/git/submodule.go

@@ -64,7 +64,6 @@ func getRefURL(refURL, urlPrefix, repoFullName, sshDomain string) string {
 		// ex: git@try.gitea.io:go-gitea/gitea
 		match := scpSyntax.FindAllStringSubmatch(refURI, -1)
 		if len(match) > 0 {
-
 			m := match[0]
 			refHostname := m[2]
 			pth := m[3]