Give pins a different window title (#3766)

* Give pins a different window title

Workaround for a KDE issue where the capture window can't be
differentiated from the pin window in any way, making the multi-monitor
workaround in #3073 also break pins.

* reformat window title

Flameshot Pin => flameshot-pin

src/tools/pin/pinwidget.cpp

@@ -39,6 +39,7 @@ PinWidget::PinWidget(const QPixmap& pixmap,
     // set the bottom widget background transparent
     setAttribute(Qt::WA_TranslucentBackground);
     setAttribute(Qt::WA_DeleteOnClose);
+    setWindowTitle("flameshot-pin");
     ConfigHandler conf;
     m_baseColor = conf.uiColor();
     m_hoverColor = conf.contrastUiColor();