Fix centering of inner circle in PhotoVideoControl

The inner circle in the PhotoVideoControl widget was not always
perfectly centered due to a mismatch in the parity of the parent and
child widths. Adjusted the width calculation of the inner circle to
ensure it has the same parity as its parent, resulting in proper
centering.

src/FlightMap/Widgets/PhotoVideoControl.qml

@@ -166,7 +166,8 @@ Rectangle {
 
                     Rectangle {
                         anchors.centerIn:   parent
-                        width:              parent.width * (_isShootingInCurrentMode ? 0.5 : 0.75)
+                        // ensure width has the same parity as parent.width so that it gets properly centered
+                        width:              Math.floor(parent.width * (_isShootingInCurrentMode ? 0.5 : 0.75) / 2) * 2 + parent.width % 2
                         height:             width
                         radius:             _isShootingInCurrentMode ? 0 : width * 0.5
                         color:              _isShootingInCurrentMode || _canShootInCurrentMode ? qgcPal.colorRed : qgcPal.colorGrey