Add tag description extract to administrator tags view

[PhilETaylor]

Pull Request for Issue #23056 .

Summary of Changes

Get tags description from the db for later output by 3rd party template overides.

Testing Instructions

Note: Coded in Github UI, not tested in php, please ensure you test correctly

see #23056

Expected result

see #23056

Actual result

see #23056

Documentation Changes Required

None

[Quy]

I have tested this item ✅ successfully on 2ebc81f

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[SharkyKZ]

I have tested this item ✅ successfully on 2ebc81f

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[infograf768]

RTC as Travis fails on 7.3 for no reason.

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