K8SPG-833: add env and envFrom fields

[pooknull]

https://perconadev.atlassian.net/browse/K8SPG-833

DESCRIPTION

This PR adds the following fields:

• .spec.instances[].env
• .spec.instances[].envFrom
• .spec.proxy.pgBouncer.env
• .spec.proxy.pgBouncer.envFrom
• .spec.backups.pgbackrest.jobs.env
• .spec.backups.pgbackrest.jobs.envFrom
• .spec.backups.pgbackrest.repoHost.env
• .spec.backups.pgbackrest.repoHost.envFrom

They have the same functionality as in the ps-operator.

Helm charts PR: percona/percona-helm-charts#590

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?

Config/Logging/Testability

• Are all needed new/changed options added to default YAML files?
• Are all needed new/changed options added to the Helm Chart?
• 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 PG version?
• Does the change support oldest and newest supported Kubernetes version?

[JNKPercona]

Test Name	Result	Time
backup-enable-disable	passed	00:07:03
custom-extensions	passed	00:09:45
custom-tls	passed	00:05:55
database-init-sql	passed	00:03:39
demand-backup	passed	00:24:33
finalizers	passed	00:03:49
init-deploy	passed	00:03:10
monitoring	passed	00:08:06
monitoring-pmm3	passed	00:07:52
one-pod	passed	00:05:51
operator-self-healing	passed	00:07:59
pgvector-extension	passed	00:02:36
pitr	passed	00:15:36
scaling	passed	00:04:53
scheduled-backup	passed	00:27:08
self-healing	passed	00:09:32
sidecars	passed	00:03:00
start-from-backup	passed	00:11:14
tablespaces	passed	00:08:12
telemetry-transfer	passed	00:03:30
upgrade-consistency	passed	00:06:42
upgrade-minor	failure	00:03:36
users	passed	00:04:26
We run 23 out of 23		03:08:18

commit: 3683dcb
image: perconalab/percona-postgresql-operator:PR-1231-3683dcb80