Steal the window back when the WM reparents it

I've seen this happen once or twice. Earlier on (in #40) we could get
away with just reparenting the window another time. But here both
reparents succeed, and the issue still happens. But a reparent notify
for `parent_window` did appear on system affected by this issue, which
is very odd. Hopefully this will help.

CHANGELOG.md

@@ -31,6 +31,10 @@ Versioning](https://semver.org/spec/v2.0.0.html).
   like FrozenPlain **Obelisk** would result in a crash.
 - Fixed a regression from yabridge 3.4.0 where JUCE-based VST3 plugins might
   cause **Ardour** or **Mixbus** to freeze in very specific circumstances.
+- When the window manager somehow steals yabridge's window away from the host,
+  yabridge will now try to steal it back and reparent it to the host's window
+  again. This very rarely happened with some window managers, like XFWM, and
+  only in certain DAWs like **Ardour**.
 - Worked around a **REAPER** bug that would cause REAPER to not process any
   keyboard input when the FX window is active but the mouse is outside of the
   window. We now use the same validation used in `xprop` and `xwininfo` to find