Replace static_casts by QOverload where possible

Mainly to get rid of the QProcess::finished deprecation warning.

Also adjust coding style in the surrounding connects when needed.

Change-Id: I12f9b248c7974b892c4a069356e578e80f8c59e9
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/autotest/testrunner.cpp

@@ -217,8 +217,7 @@ void TestRunner::scheduleNext()
     }
     m_currentProcess->setProcessEnvironment(environment.toProcessEnvironment());
 
-    connect(m_currentProcess,
-            static_cast<void (QProcess::*)(int, QProcess::ExitStatus)>(&QProcess::finished),
+    connect(m_currentProcess, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
             this, &TestRunner::onProcessFinished);
     const int timeout = AutotestPlugin::settings()->timeout;
     QTimer::singleShot(timeout, m_currentProcess, [this]() { cancelCurrent(Timeout); });