DBaaS: Percona Operators inside Kubernetes cluster managed by PMM can now be upgraded

User story:
As a PMM admin, I need to be able to update k8s operators in my K8s cluster so that I can leverage fixes and new features coming with this version of the operator

UI/UX:
TBD

Acceptance criteria

• User can initiate Operator upgrade
• User able to see the progress/status of the Upgrade process
• upgrade operator to N+1 version 
• user able to see the logs of the upgrade operation 
• Other related components also updated 

Out of scope:

• expose the new features on PMM UI without pmm server update
• update of the operator without user interaction
• Rolling several upgrades at once

Suggested implementation:
TBD

How to test:
FB: https://github.com/Percona-Lab/pmm-submodules/pull/1901

1. Register Kubernetes cluster, Kubernetes list should show there are operators installed.
2. Delete operator installed when registering the cluster: curl -L https://raw.githubusercontent.com/percona/percona-xtradb-cluster-operator/v1.8.0/deploy/bundle.yaml | kubectl delete -f -
3. Wait until it's deleted and apply old operator: curl -L https://raw.githubusercontent.com/percona/percona-xtradb-cluster-operator/v1.7.0/deploy/bundle.yaml | kubectl apply -f -
4. Create database cluster with old version of operator, we will need this later:  

   curl 'http://localhost/v1/management/DBaaS/XtraDBCluster/Create' -H 'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:89.0) Gecko/20100101 Firefox/89.0' -H 'Accept: application/json, text/plain, */*' -H 'Accept-Language: en-US,en;q=0.5' --compressed -H 'Content-Type: application/json;charset=utf-8' -H 'Origin: https://localhost' -H 'Connection: keep-alive' -H 'Referer: https://localhost/graph/dbaas/dbclusters' -H 'Cookie: grafana_session=3c8c0b0ab4665ec5a4828237b71834ac' -H 'TE: Trailers' --data-raw '{"kubernetes_cluster_name":"minikube","name":"dbcluster","params":{"cluster_size":3,"pxc":{"compute_resources":{"cpu_m":1000,"memory_bytes":1000000000},"disk_size":1000000000,"image":"percona/percona-xtradb-cluster:8.0.21-12.1"},"haproxy":{"compute_resources":{"cpu_m":1000,"memory_bytes":2000000000}}}}'
   

5. At kubernetes listing page, you should see there is an update available for pxc operator. Triger the upgrade.
6. You should see old operator pod getting terminated, new starting up. Check the image of the new operator pod to see it's really 1.8.0.
7. Also the database cluster created in point 4. should contain updated versions of images and also CRVersion should be updated. Basically everywhere where was mentioned older version of operator '1.7.0' should be now '1.8.0'.

Details:
TBD