Selector: Firefox 114 fails the ":lang respects escaped backslashes" selector test

[mgol]

Description

Firefox 114 fails the ":lang respects escaped backslashes" selector test. We should fix it before releasing 3.7.1.

Link to test case

https://swarm.jquery.org/result/4756651

[ewolfman]

hi @mgol - general question not necessarily related to this issue - when is jQuery 3.7.1 scheduled to be released? (under the 3.7.1 milestone it says "No due date").

[mgol]

@ewolfman We don't promise any dates, it'll be released when we're ready. In particular, all issues under the milestone must be closed.

[mgol]

I submitted a bug report to Mozilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1839747

[mgol]

PR disabling the problematic test: #5277