[e2e] Remove test that old version of wdio can't handle
Description
In chrome 127, we needed to adapt to catch alerts triggered by window.onbeforeunload. This was fixed in !843 (merged).
However, with chrome 128, this fix doesn't work anymore.
I found no way of handling this, and I simply do not understand why the fix is now insufficient. Since this is a small part of the legacy frontend, I vote to remove the test.