uitests: Make hotplug test pass on both f37 and f38

Signed-off-by: Cole Robinson <crobinso@redhat.com>

tests/uitests/test_livetests.py

@@ -471,11 +471,15 @@ def _testLiveHotplug(app, fname):
     lib.utils.check(lambda: tab.showing)
     entry.set_text(fname)
     appl.click()
+    # pylint: disable=unreachable
+    import dogtail.tree
+    try:
         # F38 CDROM change is broken:
         # https://gitlab.com/qemu-project/qemu/-/issues/933
-    # pylint: disable=unreachable
         app.click_alert_button("changes will take effect", "OK")
         return
+    except dogtail.tree.SearchError:
+        pass
 
     lib.utils.check(lambda: not appl.sensitive)
     lib.utils.check(lambda: entry.text == fname)