[Cleanup] Unused #includes (#6367)

* [Cleanup] Unused #includes

Took 44 minutes

* [Cleanup] More unused #includes

Took 55 minutes

* [Cleanup] Include QSet

Took 4 minutes

* [Cleanup] Include QDebug in deck_list.cpp

Took 3 minutes

* [Cleanup] Include protocol stuff in servatrice_database_interface.h

Took 3 minutes

* [Cleanup] Include QDialogButtonBox

Took 8 minutes

* [Cleanup] Include QUrl

Took 8 minutes

* [Cleanup] Include QTextOption in header.

Took 3 minutes

* [Cleanup] Include QMap in user_list_manager.h

Took 8 minutes

* [Cleanup] Adjust qjson

Took 8 minutes

* [Cleanup] include button box.

Took 3 minutes

* [Cleanup] Redo fwd declarations.

* [Cleanup] Redo last removed fwd declarations.

---------

Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

libcockatrice_settings/libcockatrice/settings/card_database_settings.h

@@ -10,9 +10,6 @@
 
 #include "settings_manager.h"
 
-#include <QObject>
-#include <QSettings>
-#include <QVariant>
 #include <libcockatrice/interfaces/interface_card_set_priority_controller.h>
 
 class CardDatabaseSettings : public SettingsManager, public ICardSetPriorityController

libcockatrice_settings/libcockatrice/settings/download_settings.h

@@ -9,8 +9,6 @@
 
 #include "settings_manager.h"
 
-#include <QObject>
-
 class DownloadSettings : public SettingsManager
 {
     Q_OBJECT

libcockatrice_settings/libcockatrice/settings/settings_manager.h

@@ -7,7 +7,6 @@
 #ifndef SETTINGSMANAGER_H
 #define SETTINGSMANAGER_H
 
-#include <QObject>
 #include <QSettings>
 #include <QStringList>
 #include <QVariant>