Run gopls modernize on codebase (#34751)

Recent modernize fixes:
https://github.com/golang/tools/commits/master/gopls/internal/analysis/modernize

routers/web/user/code.go

@@ -5,6 +5,7 @@ package user
 
 import (
 	"net/http"
+	"slices"
 
 	"code.gitea.io/gitea/models/db"
 	repo_model "code.gitea.io/gitea/models/repo"
@@ -87,11 +88,8 @@ func CodeSearch(ctx *context.Context) {
 		loadRepoIDs := make([]int64, 0, len(searchResults))
 		for _, result := range searchResults {
 			var find bool
-			for _, id := range loadRepoIDs {
-				if id == result.RepoID {
-					find = true
-					break
-				}
+			if slices.Contains(loadRepoIDs, result.RepoID) {
+				find = true
 			}
 			if !find {
 				loadRepoIDs = append(loadRepoIDs, result.RepoID)