fix: time tooltip out of bounds on the right

This revives
videojs#7308

The analysis by @PikachEXE
videojs#7248 (comment)
still stands.

However, the alignment issues pointed out in
videojs#7308 (comment)
cannot be reproduced with the current Video.js v8.x and v7.x versions
after the patch is applied.

src/js/control-bar/progress-control/progress-control.js

@@ -72,7 +72,7 @@ class ProgressControl extends Component {
     }
 
     const seekBarEl = seekBar.el();
-    const seekBarRect = Dom.findPosition(seekBarEl);
+    const seekBarRect = Dom.getBoundingClientRect(seekBarEl);
     let seekBarPoint = Dom.getPointerPosition(seekBarEl, event).x;
 
     // The default skin has a gap on either side of the `SeekBar`. This means