[clang] [clang][NFC] Refactor `Sema::TemplateDeductionResult` (PR #81398)

[Vlad Serebrennikov via cfe-commits]

================
@@ -295,6 +297,10 @@ struct DeductionFailureInfo {
 
   /// Free any memory associated with this deduction failure.
   void Destroy();
+
+  TemplateDeductionResult getResult() const {
+    return static_cast<TemplateDeductionResult>(Result);
----------------
Endilll wrote:

@erichkeane This is also worth checking. Code itself is boring, but the approach might be not.

https://github.com/llvm/llvm-project/pull/81398