Ship maximised widgets and remove feature flag

[jryans]

Maximised widgets has now been reviewed by Design and Product, and has been approved for release.

We should remove the feature flag so it's available for everyone:

• Remove the setting
• Remove all getValue lines that test for the feature
• Remove the feature from the labs documentation
• Update issue automation to not add Z-Labs to A-Widgets and remove Z-Labs from any outstanding issues at the point of release #20485

[kittykat]

I've added a fourth point about housekeeping in the repo 👍

[toger5]

Update issue automation to not add Z-Labs to A-Widgets and remove Z-Labs from any outstanding issues at the point of release

I hope I got this right: #20483

[jryans]

All done! 🥳