Fix7334 Disallow async in functionExpression and ArrowFunction (#9062)

* Error when using async modifier in function-expression and arrow-function when target es5

* Add tests and baselines

src/compiler/checker.ts

@@ -17794,6 +17794,8 @@ namespace ts {
                 case SyntaxKind.ImportEqualsDeclaration:
                 case SyntaxKind.ExportDeclaration:
                 case SyntaxKind.ExportAssignment:
+                case SyntaxKind.FunctionExpression:
+                case SyntaxKind.ArrowFunction:
                 case SyntaxKind.Parameter:
                     break;
                 case SyntaxKind.FunctionDeclaration: