azure_rm_containerservice (ansible#33597)

* add acr

* acr

* acr

* fix a minor error

* add tests and fixes as suggested

* use get_mgmt_svc_client to enable bi

* fixes as zim suggested

* code refinement

* get acr instance before update

* fix a bug

* remove Classic sku as it's going to deprecate

* pass sanity test

* fix sanity

* fixes based on comments

* fix broken namespace unregistered error

* fix a bug

* fix a bug

* fix

* add register namespace

* fixes tests

* remove pdb

* add ci azure test

* removed required: false

* renamed acr -> containerregistry

* fixed spelling mistake

* fixed idempotence

* fix for idempotence was wrong

* fixed a few issues

* different log when exception different than ResourceNotFound

* self.fail instead of log

* updated sample return value

* added login server in results

* fixed else

* fixed line too long

* cmp -> __ne__

* fixed trailing whitespace

* output.changed is false when instance updated

* fix for state change

* one more update

* update instance only when location or sku has changed

* fixed syntax error

* fixed acr test

* just removed unnecessary comment to trigger ci

* update return value shape

* flatten `state`
* change credential dictionary state
* add credentials to integration tests