Fix AST dump generation for enum_is_case_expr

AST Dumper at the moment generates invalid AST dump output for `enum_is_case_expr`
Currently it `forgets` to add a closing bracket, which leads to unparsable AST dump output.
```
          (if_stmt implicit\
            (call_expr implicit type='Int1' nothrow arg_labels=\
              (dot_syntax_call_expr implicit type='() -> Int1' nothrow\
                (declref_expr implicit type='(Bool) -> () -> Int1' decl=Swift.(file).Bool._getBuiltinLogicValue() function_ref=double)\
                (enum_is_case_expr implicit type='Bool' some\
                  (declref_expr implicit type='UIBarButtonItem?' decl=The.(file).Controller.<anonymous>.tmp1 direct_to_storage function_ref=unapplied))\                   # <--- One Bracked is missing here
              (tuple_expr implicit type='()'))\
            (return_stmt implicit\
              (force_value_expr implicit type='UIBarButtonItem'\
                (declref_expr implicit type='UIBarButtonItem?' decl=The.(file).Controller.<anonymous>.tmp1 direct_to_storage function_ref=unapplied))))\
```

Author: PaulTaykalo

lib/AST/ASTDumper.cpp

@@ -2343,7 +2343,7 @@ class PrintExpr : public ExprVisitor<PrintExpr> {
     printCommon(E, "enum_is_case_expr") << ' ' <<
       E->getEnumElement()->getName() << "\n";
     printRec(E->getSubExpr());
-    
+    PrintWithColorRAII(OS, ParenthesisColor) << ')';
   }
   void visitUnresolvedPatternExpr(UnresolvedPatternExpr *E) {
     printCommon(E, "unresolved_pattern_expr") << '\n';