Move dev widget empty state behind alpha FF and promote list to beta FF

What does this MR do and why?

As per the comment , we are moving the dev widget to work_items_beta FF and putting the empty action CTA's behind work_items_alpha FF.

work_items_beta FF	work_items_alpha FF	empty state visible	Dev widget visible
ON	ON	YES	YES
ON	OFF	NO	YES
OFF	ON	NO	NO
OFF	OFF	NO	NO

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

work_items_beta FF	work_items_alpha FF	empty state visible	Dev widget visible
ON	ON
ON	OFF
OFF	ON
OFF	OFF

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Toggle work_items_alpha and work_items_beta as mentioned in the matrix and verify that the dev widget and empty list CTA buttons are rendered or not as expected