* Clarify that backport/no-backport is an internal thing

A few times per month, external contributors ask about the notion doc they can't access and about the labels they are not expected to set. This is not the experience we should give to people who not only take their time to contribute to metabase, but also actually read the PR template.

(slightly duplicated condition in the beginning and the end of the paragraph — "For those employed [...] If you're not employed [...]" — is on purpose)

* Add linebreaks in PR template

Co-authored-by: Tim Macdonald <tim@metabase.com>

---------

Co-authored-by: Tim Macdonald <tim@metabase.com>

* Update PR template

* review

* Fix some Eastwood failures

* Fix a lot of Eastwood errors now that it runs against test namespaces [ci skip]

* Run Eastwood against test namespaces [WIP]

* Bump Eastwood version to fix some errors in Eastwood itself

* Fix another lint warning

* Fix test failure

* More test fixes 

* Fix all the warnings!

* Test fix 

* Bump Eastwood GH action timeout to 20 minutes (!)

This completes one step towards removing Enzyme.
The complete list of all tests is at #13657.

* Run each test in isolation

* Convert `EditUserModal.integ.spec.js` to Cypress

* Convert `PeopleListingApp.integ.spec.js` to Cypress

* Convert `GroupDetailApp.integ.spec.js` to Cypress

* Delete `GroupsListingApp.integ.spec.js`

It was already covered in Cypress.

* Delete `NewUserModal.integ.spec.js`

It was already covered in Cypress.

* Convert `UserActivationModal.integ.spec.js`

* Convert `UserPasswordResetModal.integ.spec.js`

* Convert `UserSettings.integ.spec.js`

* Remove integration tests

* Remove integration tests from CI

* Fix linter errors

* Delete `AuditTable.integ.spec.jsx`

* Clean up `people.cy.spec.js`

* Update assertion that makes sure XHR didn't happen

* Remove redundant command from PR template

Note: `yarn-lint` already runs `yarn flow`.
https://github.com/metabase/metabase/pull/14174#discussion_r549790198

* Remove explicit mention of timezones in `developers-guide.md`

* improve i18n workflow documentation

* fix a typo

* clear up copy