UI small fixes

[oliveirarleo]

Hi guys, sorry for the delay, I ended up going on a trip as I am in my vacation.

Validation Steps

• Simply open the pages for workflow, history and settings page, the projects menu will be hidden when there is no project assigned yet.
• In the workflow job editor page, there is no flickering. reference for the original bug https://www.loom.com/share/58feb3af170a42fdbe70a127843bb7cb
• The save button still blinks, but does not change size, the user does not have time to read still.
• Some texts are standardized with ... for the phx-disable-with text.
• It's unclear if other buttons are flickering, I am new to this project, and did not find other pages with the same problems, but reading the code they should exist.

Notes for the reviewer

At the lib/lightning_web/live/components/menu.ex, github fails to diff in a good way. You can notice that the previous code is the same as in the else block, this should simplify the review.

Related issue

Fixes #2212

Review checklist

• [x] I have performed a self-review of my code
• [x] I have verified that all appropriate authorization policies (:owner, :admin, :editor, :viewer) have been implemented and tested
• [x] If needed, I have updated the changelog
• [ ] Product has QA'd this feature