QbsProject: Use base Project::isParsing() function

While the base function is not virtual the "hiding" re-implementation
effectively appears to do the same. So drop it.

Change-Id: I4ab0e0690b948ce3f590c87262d10622b169450e
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/qbsprojectmanager/qbsproject.cpp

@@ -405,11 +405,6 @@ QString QbsProject::profileForTarget(const Target *t) const
     return QbsManager::profileForKit(t->kit());
 }
 
-bool QbsProject::isParsing() const
-{
-    return m_qbsUpdateFutureInterface;
-}
-
 bool QbsProject::hasParseResult() const
 {
     return qbsProject().isValid();