chore: fix legacy git ref problems (#38827)

1. add correct "refs/heads" prefix to the branch name for commit graph
2. fix incorrect cache key in GetCommitGraphsCount
3. remove the "--" trim for the tag name, there is no security vulnerability, we never do so anywhere else

Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

services/release/release.go

@@ -90,8 +90,6 @@ func createTag(ctx context.Context, gitRepo *git.Repository, rel *repo_model.Rel
 				return false, fmt.Errorf("GetProtectedTags: %w", err)
 			}
 
-			// Trim '--' prefix to prevent command line argument vulnerability.
-			rel.TagName = strings.TrimPrefix(rel.TagName, "--")
 			isAllowed, err := git_model.IsUserAllowedToControlTag(ctx, protectedTags, rel.TagName, rel.PublisherID)
 			if err != nil {
 				return false, err