24 hour format

[aeter]

SUMMARY

Related: #15005, #11531

(continues PR #15186 )

Adds 24 hour format across the user interface. Configurable at the Settings page, using a dropdown.

ISSUE TYPE

• New or Enhanced Feature

COMPONENT NAME

• API
• UI

AWX VERSION

make VERSION
awx: 

ADDITIONAL INFORMATION

I'm sorry, this seems like a big PR.
I don't like passing useConfig() everywhere. Do you think using a cookie (set at login) would be better?
I've ran throught the UI, seemed OK.

Ran these (the tests passed):

npm run prettier
npm run lint
npm run test
make black

[aeter]

settings dropdown:

example page (schedules) with 24-hour format:

[aeter]

I'm ready to rework the code, if you think the implementation is not good, or any details need changing.

So, at first it seemed using something like zustand would make sense here - like, setting datetime_format on login and then reading it from the util/dates.js. Then the PR would touch like 10 files instead of 53, as the formatDateTime signature wouldn't change. But I didn't want to introduce such a dependency to your project - without even discussing, but just inserting it into the code. Anyway.