(cherry picked from commit 40f27f908a)

* fix: Add updated datepicker; fixed seconds formatting bug.
Seconds between 0 and 9 were not zero-padded.

* feat: Add framework for time format

* feat: datetime server-side formatters.

* tests: Added server-side datetime formatter tests

* feat: Update client-side datetime formatters

* tests: Add Cypress client-side formatting tests.

* fix: JSON errors

* fix: Update to not hard-code admin password

* fix: Change to using bulk_update rather than the REST API

* tests: Use Custom doctype for testing, not Standard

* fix: Codacy style fixes

* fix: Commonify update_datetime_picker in date.js, datetime.js, time.js
Fix order of time_format in System Settings
Restore get_user_fmt in utils/datetime.js

* feat: Drastically reduce scale of Cypress testing (to make tests faster)
Full testing is possible by setting 'fast_mode' to false in the spec file.

* fix: Fix issues with datepicker/timepicker expansion

* fix: typo

* style: Various style fixes as requested by DeppSource: Python

* fix: Timepicker not hiding on 'now' button. Force hiding on click.

* style: Codacy style fixes.

* fix: Use datepicker from node_modules

* test: Refactor Datetime UI tests

- cy.get_field
- cy.set_value
- cy.insert_doc with ignore_duplicate
- Nominal datetime tests to cover most formats
- Formatting with prettier

* test: Datetime UI tests; wait for cur_frm.doc.datetime to update

* tests: Add whitespace to typed input

- Clear input only for Time field

* test: Wait timeout 200

* test: Fix form test

Co-authored-by: Faris Ansari <netchampfaris@users.noreply.github.com>