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

tests/e2e/e2e_test.go

@@ -106,18 +106,20 @@ func TestE2e(t *testing.T) {
 				cmd := exec.Command(runArgs[0], runArgs...)
 				cmd.Env = os.Environ()
 				cmd.Env = append(cmd.Env, fmt.Sprintf("GITEA_URL=%s", setting.AppURL))
+
 				var stdout, stderr bytes.Buffer
 				cmd.Stdout = &stdout
 				cmd.Stderr = &stderr
+
 				err := cmd.Run()
 				if err != nil {
 					// Currently colored output is conflicting. Using Printf until that is resolved.
 					fmt.Printf("%v", stdout.String())
 					fmt.Printf("%v", stderr.String())
 					log.Fatal("Playwright Failed: %s", err)
-				} else {
-					fmt.Printf("%v", stdout.String())
 				}
+
+				fmt.Printf("%v", stdout.String())
 			})
 		})
 	}