[clang] [clang][ExprConst] Don't try to evaluate value-dependent DeclRefExprs (PR #67778)

[Mariya Podchishchaeva via cfe-commits]

================
@@ -177,3 +177,16 @@ namespace LambdaCallOp {
     p();
   }
 }
+
+/// This used to crash due to an assertion failure,
+/// see gh#67690
----------------
Fznamznon wrote:

NIT, why three slashes? 
```suggestion
// This used to crash due to an assertion failure,
// see gh#67690
```

https://github.com/llvm/llvm-project/pull/67778