CppEditor: Add second "Find References" Action

This one includes access type categorization, while the "normal" one
does not.
We need this now, because with clangd, the categorization is too slow to
enable it by default.

Change-Id: I2eb4608630d34452ae28f0836befd5d9053f42bf
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangcodemodel/test/clangdtests.cpp

@@ -147,6 +147,7 @@ ClangdTestFindReferences::ClangdTestFindReferences()
 void ClangdTestFindReferences::initTestCase()
 {
     ClangdTest::initTestCase();
+    CppTools::codeModelSettings()->setCategorizeFindReferences(true);
     connect(client(), &ClangdClient::foundReferences, this,
             [this](const QList<SearchResultItem> &results) {
         if (results.isEmpty())