fix(diff): pass the context to OpenRepositoryLocal in the tail section test

OpenRepositoryLocal gained a cat-file batch context parameter in #38684,
which broke the build of this package's tests after rebasing onto main.

Assisted-by: Codet

Author: lunny

services/gitdiff/gitdiff_test.go

@@ -650,7 +650,7 @@ func TestGetDiffForRender_TailSectionLineCounts(t *testing.T) {
 	beforeContent := buildContent("")
 	afterContent := buildContent("line 05 CHANGED")
 
-	gitRepo, err := git.OpenRepositoryLocal(repoDir)
+	gitRepo, err := git.OpenRepositoryLocal(t.Context(), repoDir)
 	require.NoError(t, err)
 	defer gitRepo.Close()