[clang] [Clang] strengthen checks for 'main' function to meet [basic.start.main] p3 requirements (PR #101853)

[Mital Ashok via cfe-commits]

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@@ -12238,7 +12255,6 @@ void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
         << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
     FD->setConstexprKind(ConstexprSpecKind::Unspecified);
   }
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MitalAshok wrote:

```suggestion
  }

```

(Unnecessary diff)

https://github.com/llvm/llvm-project/pull/101853