Fix extensions tabs following deprecation of old tab code

[mattwire]

Overview

Fix extensions tabs following changes in #19066

Before

Tabs stopped rendering on extensions page.

After

Tabs load and selectedChild works.

Technical Details

Add tab javascript resource.

Comments

@demeritcowboy @colemanw This is the fix I think!

[civibot]

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[demeritcowboy]

Thanks. Works for me!

[eileenmcnaughton]

@mattwire @demeritcowboy - quick work! Can you confirm

1. can we close the issue
2. this is against master - should it be against the rc (which was only cut a few days ago)

[demeritcowboy]

The other PR was merged yesterday so it's just master.

The lab ticket can close just needs a milestone - doesn't seem to be a 5.34 available.

[eileenmcnaughton]

Created - @mlutfy can we make it so Dave can create milestones?

[mlutfy]

@eileenmcnaughton On Gitlab or Github? (Gitlab should be easy, but I don't know for Github)

[demeritcowboy]

Gitlab. An alternative is add it to the release tasklist to create a new label for whatever the new master is. Not sure where that list/script lives. Maybe this should be its own ticket.