CMakePM: Refactor "Initial Parameters" as a tab bar item

Now we have "Initial Configuration" and "Current Configuration"
as tab bar buttons.

This way the UI can be shared between the two configuration states.

Task-number: QTCREATORBUG-26869
Change-Id: I8206032a2a5ac076629865057816edb99706f2ff
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/plugins/cmakeprojectmanager/builddirparameters.h

@@ -61,7 +61,8 @@ public:
     Utils::Id cmakeToolId;
 
     QStringList initialCMakeArguments;
-    QStringList extraCMakeArguments;
+    QStringList configurationChangesArguments;
+    QStringList additionalCMakeArguments;
 };
 
 } // namespace Internal