Use sentence case for tooltips

[mapk]

Description

Fixes #16764 in part. I believe I've found all the tooltip instances that used title case and switched them to sentence case. I have not changed the labels in the popovers yet. I'm thinking that could be another PR to keep things simple. I'm starting to fiddle with a lot of files and it feel uncomfortable.

cc: @gziolo, I'd love to get your eyes on this to make sure I edited the correct files. If there are others I need to edit, let me know.

How has this been tested?

Locally.

Screenshots

Before:

After:

Types of changes

Non-breaking change.

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.

[gziolo]

Nice, some tests need to be updated as they apparently depend on those labels :)

[mapk]

Looks like @senadir updated some snapshots for me! Thanks! 💯

@gziolo I'm not sure how to correct the tests that need updating. Is this something you can guide me through?

[senadir]

test still fails for some reason, Ithough I fixed all the outstanding issues, seems new ones showed up, I will restart the tests and see

as for finding the issues, you can go to the failed test building the "Details" link on right on the Travis check and then opening the failed job (ignore jobs that are allowed to fail)

you will have a long log, the failed checks are the ones that start with FAIL beside it, you will find the corresponding file to test, like

FAIL packages/e2e-tests/specs/adding-inline-tokens.test.js 
FAIL packages/e2e-tests/specs/block-transforms.test.js

[kjellr]

This is a solid update, and it looks like the tests are now passing. Thanks, @mapk and @senadir!