AutoTest: Provide way to remember last chosen run configurations

In some special setups it is almost impossible to get the right
executable or run configuration. For bigger projects this can
become a pain point when trying to execute tests and always
getting asked which one to run.
So, allow remembering the choice and use it if appropriate.
The cached information is not stored permanently.

Resetting of the cached information can also be triggered by
switching or closing the current project and inside the settings.

Task-number: QTCREATORBUG-20859
Change-Id: If416ea0ae9ad3548daca2ffcf5888fd568fd2622
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/autotest/testsettingspage.cpp

@@ -29,6 +29,7 @@
 #include "testsettingspage.h"
 #include "testsettings.h"
 #include "testtreemodel.h"
+#include "autotestplugin.h"
 
 #include <coreplugin/icore.h>
 #include <utils/fancylineedit.h>
@@ -139,6 +140,8 @@ TestSettingsWidget::TestSettingsWidget(QWidget *parent)
         m_ui.editFilter->setEnabled(enable);
         m_ui.removeFilter->setEnabled(enable);
     });
+    connect(m_ui.resetChoicesButton, &QPushButton::clicked,
+            this, [] { AutotestPlugin::clearChoiceCache(); });
 }
 
 void TestSettingsWidget::setSettings(const TestSettings &settings)