[clang] [clang] fix lack comparison of declRefExpr in ASTStructuralEquivalence (PR #66041)

[Ding Fei via cfe-commits]

================
@@ -2320,5 +2320,14 @@ TEST_F(StructuralEquivalenceStmtTest, UnresolvedLookup) {
   EXPECT_TRUE(testStructuralMatch(t));
 }
 
+TEST_F(StructuralEquivalenceStmtTest, DeclRefENoEq) {
----------------
danix800 wrote:

```suggestion
TEST_F(StructuralEquivalenceStmtTest, DeclRefExpr) {
```

https://github.com/llvm/llvm-project/pull/66041