Update jQuery to v3.6.1.

[yubiuser]

What does this PR aim to accomplish?:

Updates jquery to the latest version 3.6.1. The release

does have some good bug fixes and improvements.

https://blog.jquery.com/2021/03/02/jquery-3-6-0-released/ and https://blog.jquery.com/2022/08/26/jquery-3-6-1-maintenance-release/

There should be no breaking changes since 3.5.1., since the last big upgrade was to 3.5.0
https://jquery.com/upgrade-guide/3.5/

I used the jquery-migrate plugin (https://github.com/jquery/jquery-migrate) to detect changes. All warnings were of type jQuery.fn.XXX() event shorthand is deprecated. (See jquery/jquery#3214 and jquery/api.jquery.com#972

I fixed those for our files but left the vendor files untouched.

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[DL6ER]

I tried to test as careful as possible and nothing seems to break with this PR. It deserves entering the broader testing things get when in devel