NetworkAccessManager: Remove unneeded includes

Change-Id: I8263984565a9eaf2393612843c2eb79ce9e118f5
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>

src/libs/utils/networkaccessmanager.cpp

@@ -4,13 +4,9 @@
 #include "networkaccessmanager.h"
 
 #include <QCoreApplication>
-#include <QLibraryInfo>
 #include <QLocale>
 #include <QNetworkReply>
-
-#ifdef Q_OS_UNIX
-#include <sys/utsname.h>
-#endif
+#include <QSysInfo>
 
 /*!
    \class Utils::NetworkAccessManager
@@ -75,5 +71,4 @@ QNetworkReply* NetworkAccessManager::createRequest(Operation op, const QNetworkR
     return QNetworkAccessManager::createRequest(op, req, outgoingData);
 }
 
-
 } // namespace utils

src/libs/utils/networkaccessmanager.h

@@ -7,10 +7,6 @@
 
 #include <QNetworkAccessManager>
 
-QT_BEGIN_NAMESPACE
-class QUrl;
-QT_END_NAMESPACE
-
 namespace Utils {
 
 class QTCREATOR_UTILS_EXPORT NetworkAccessManager : public QNetworkAccessManager