fix: call select2 as it is a AMD module

[puehringer]

Developer Checklist (Definition of Done)

Issue

• All acceptance criteria from the issue are met
• Tested in latest Chrome/Firefox

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Summary of changes

• Explicitly call select2 after importing jQuery to ensure it is loaded and available.
• See Using Select2 with npm / webpack resolves in JS Error "Cannot read properties of undefined (reading 'getAttribute') at Object.Utils.GetUniqueElementId" select2/select2#6146 for details.

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Thanks for creating this pull request 🤗

[thinkh]

I tested this branch in Ordino and it restores the original Select2 functionality in the rspack branch.