CppTools: modernize

Change-Id: Iaf02e4d026f1ac8b216833d83cd7a735e21ff60a
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/cpptools/cppmodelmanagerinterface.h

@@ -35,6 +35,6 @@ public:
     virtual ProjectPart::Ptr projectPartForId(const QString &projectPartId) const = 0;
 
 protected:
-    ~CppModelManagerInterface() = default;
+    virtual ~CppModelManagerInterface() = default;
 };
 }