K8SPXC-1301: Run operator locally

[inelpandzic]

CHANGE DESCRIPTION

Problem:
The operator should be able to run on a local machine against a deployed K8S cluster.

The solution introduces two env vars:
OPERATOR_NAMESPACE - namespace in which the operator is running. If not present, the operator will read it from /var/run/secrets/kubernetes.io/serviceaccount/namespace

DISABLE_WEBHOOK - used only when the operator runs locally. This is needed since in order to set up the webhook we need the operator deployment object, but since we are running locally, that is not available.

This PR also fixes #1511

CHECKLIST

Jira

• Is the Jira ticket created and referenced properly?
• Does the Jira ticket have the proper statuses for documentation (Needs Doc) and QA (Needs QA)?
• Does the Jira ticket link to the proper milestone (Fix Version field)?

Tests

• Is an E2E test/test case added for the new feature/change?
• Are unit tests added where appropriate?
• Are OpenShift compare files changed for E2E tests (compare/*-oc.yml)?

Config/Logging/Testability

• Are all needed new/changed options added to default YAML files?
• Are the manifests (crd/bundle) regenerated if needed?
• Did we add proper logging messages for operator actions?
• Did we ensure compatibility with the previous version or cluster upgrade process?
• Does the change support oldest and newest supported PXC version?
• Does the change support oldest and newest supported Kubernetes version?

[egegunes]

@inelpandzic please fix conflicts and check tests

[JNKPercona]

Test name	Status
affinity-8-0	passed
auto-tuning-8-0	passed
cross-site-8-0	failure
demand-backup-cloud-8-0	passed
demand-backup-encrypted-with-tls-8-0	passed
demand-backup-8-0	passed
haproxy-5-7	passed
haproxy-8-0	passed
init-deploy-5-7	passed
init-deploy-8-0	passed
limits-8-0	passed
monitoring-2-0-8-0	passed
one-pod-5-7	failure
one-pod-8-0	failure
pitr-8-0	passed
pitr-gap-errors-8-0	passed
proxy-protocol-8-0	failure
proxysql-sidecar-res-limits-8-0	passed
recreate-8-0	passed
restore-to-encrypted-cluster-8-0	passed
scaling-proxysql-8-0	passed
scaling-8-0	passed
scheduled-backup-5-7	passed
scheduled-backup-8-0	passed
security-context-8-0	passed
smart-update1-8-0	failure
smart-update2-8-0	passed
storage-8-0	passed
tls-issue-cert-manager-ref-8-0	passed
tls-issue-cert-manager-8-0	failure
tls-issue-self-8-0	passed
upgrade-consistency-8-0	passed
upgrade-haproxy-8-0	passed
upgrade-proxysql-8-0	failure
users-5-7	passed
users-8-0	failure
validation-hook-8-0	passed
We run 37 out of 37

commit: 1ed4605
image: perconalab/percona-xtradb-cluster-operator:PR-1522-1ed4605b