Draft: Remove columnClass from table fields

What does this MR do and why?

Follow-up from !136807 (comment 1647748233):

Ps. I see columnClass in other places of the code, feel free to have a look and see if we should remove those too 👍

columnClass isn't defined in fields for gl-table. We can remove these lines, or replace them with tdClass when applicable.

Screenshots or screen recordings

TODO

How to set up and validate locally

TODO

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