OutputPane: Use setter for priority and fix default visibility

Do not show the buttons of output views with priority < 0 (instead of
only == -1). Reduce the number of buttons that are shown by default to
the essential ones.

Change-Id: I5b44f18537b3033ce9d616f044a8b54b76988783
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

src/plugins/autotest/testresultspane.cpp

@@ -76,6 +76,7 @@ TestResultsPane::TestResultsPane(QObject *parent) :
 {
     setId("TestResults");
     setDisplayName(Tr::tr("Test Results"));
+    setPriorityInStatusBar(-30);
     m_outputWidget = new QStackedWidget;
     QWidget *visualOutputWidget = new QWidget;
     m_outputWidget->addWidget(visualOutputWidget);
@@ -276,11 +277,6 @@ QList<QWidget *> TestResultsPane::toolBarWidgets() const
     return result;
 }
 
-int TestResultsPane::priorityInStatusBar() const
-{
-    return -666;
-}
-
 void TestResultsPane::clearContents()
 {
     m_filterModel->clearTestResults();