Add new integration Discovergy (#54280)

* Add discovergy integration

* Capitalize measurement type as it is in uppercase

* Some logging and typing

* Add all-time total production power and check if meter has value before adding it

* Add tests for Discovergy and changing therefor library import

* Disable phase-specific sensor per default, set user_input as default for schema and implement some other suggestions form code review

* Removing translation, fixing import and some more review implementation

* Fixing CI issues

* Check if acces token keys are in dict the correct way

* Implement suggestions after code review

* Correcting property function

* Change state class to STATE_CLASS_TOTAL_INCREASING

* Add reauth workflow for Discovergy

* Bump pydiscovergy

* Implement code review

* Remove _meter from __init__

* Bump pydiscovergy & minor changes

* Add gas meter support

* bump pydiscovergy & error handling

* Add myself to CODEOWNERS for test directory

* Resorting CODEOWNERS

* Implement diagnostics and reduce API use

* Make homeassistant imports absolute

* Exclude diagnostics.py from coverage report

* Add sensors with different keys

* Reformatting files

* Use new naming style

* Refactoring and moving to basic auth for API authentication

* Remove device name form entity name

* Add integration type to discovergy and implement new unit of measurement

* Add system health to discovergy integration

* Use right array key when using an alternative_key & using UnitOfElectricPotential.VOLT

* Add options for precision and update interval to Discovergy

* Remove precision config option and let it handle HA

* Rename precision attribute and remove translation file

* Some formatting tweaks

* Some more tests

* Move sensor names to strings.json

* Redacting title and unique_id as it contains user email address

CODEOWNERS

@@ -275,6 +275,8 @@ build.json @home-assistant/supervisor
 /homeassistant/components/discogs/ @thibmaek
 /homeassistant/components/discord/ @tkdrob
 /tests/components/discord/ @tkdrob
+/homeassistant/components/discovergy/ @jpbede
+/tests/components/discovergy/ @jpbede
 /homeassistant/components/discovery/ @home-assistant/core
 /tests/components/discovery/ @home-assistant/core
 /homeassistant/components/dlink/ @tkdrob