fix: django admin select2

[ambroiseRabier]

This solves: https://discuss.openedx.org/t/how-to-create-a-programs-in-discovery/18666/2 (contains images describing the issue)

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[iloveagent57]

An alternative (very similar) proposed approach to this issue: #4718
But fundamentally, we have to drop DAL as a dependency, it's not django 5 compatible and appears unmaintained.

[mphilbrick211]

Hi @ambroiseRabier! Welcome, and thank you for this contribution! In order for your CLA check to turn green, you'll need to submit a CLA form. If you are contributing as an individual, please fill out the individual CLA form here.

If you are contributing on behalf of an organization, please have your manager reach out to oscm@axim.org so you may be added to your org's existing entity agreement.

Please let me know if you have any questions. Thanks!

[e0d]

@ambroiseRabier it looks like there are some test failures, can you have a look?

[ambroiseRabier]

Well, I spent time fixing the tests, but it seems #4718 fixed the same issue 10 days ago.