Fix ParenExpr consistency test failures

Author: owen-mc

go/ql/lib/semmle/go/controlflow/ControlFlowGraphShared.qll

@@ -440,6 +440,12 @@ module GoCfg {
       // "invocation" node (and hence no inline exceptional-exit edge) is
       // created at the `defer` statement.
       e = any(Go::DeferStmt s).getCall()
+      or
+      // Parenthesized expressions are value-transparent (via `propagatesValue`)
+      // and should not get an in-order evaluation node. Marking them as
+      // pre-order prevents the shared library from auto-computing
+      // `postOrInOrder` for them (which would create an unreachable In node).
+      e instanceof Go::ParenExpr
     }
 
     predicate propagatesValue(Ast::AstNode child, Ast::AstNode parent) {