UI: Use QGroupBox::toggled signal for group changes

The QGroupBox::clicked is specifically for mouse clicks. This means that
it's not emitted if the "checked" property is modified through other
means than the mouse, for example programatically or through
accessibility software like VoiceOver.
However, we do want to catch such events, so the QGroupBox::toggle
signal (which as per the Qt documentation is the notified signal for the
"checked" property) is the appropriate one to use.

UI/window-basic-settings.cpp

@@ -334,7 +334,7 @@ void RestrictResetBitrates(initializer_list<QComboBox *> boxes, int maxbitrate);
 #define EDIT_CHANGED    &QLineEdit::textChanged
 #define CBEDIT_CHANGED  &QComboBox::editTextChanged
 #define CHECK_CHANGED   &QCheckBox::clicked
-#define GROUP_CHANGED   &QGroupBox::clicked
+#define GROUP_CHANGED   &QGroupBox::toggled
 #define SCROLL_CHANGED  &QSpinBox::valueChanged
 #define DSCROLL_CHANGED &QDoubleSpinBox::valueChanged