Release 2.8.1

[eleo007]

CHANGE DESCRIPTION

This PR merges back the release-2.8.1 branch back to main. It:

1. upgrade-consistency test to use 2.8.1 crVersion
2. adds major upgrade test for PG8.0 and sets custom extension version to 1.6.6 as PG8 is not supported by earlier versions.
3. Adds changes to allow creating perconapgupgrade resource with PG17 (fromPostgresVersion.maximum=17)
4. Upgrades custom-tls test to have bigger timeout as PG8 tests were too flaky (seems PG8 needs more time for cert upgrade & start).

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?

[egegunes]

this kind of PRs require description too

[JNKPercona]

Test Name	Result	Time
backup-enable-disable	passed	00:06:27
custom-envs	passed	00:18:29
custom-extensions	passed	00:14:24
custom-tls	passed	00:06:42
database-init-sql	passed	00:02:17
demand-backup	passed	00:28:14
finalizers	passed	00:03:37
init-deploy	passed	00:02:51
monitoring	passed	00:07:53
monitoring-pmm3	passed	00:08:17
one-pod	passed	00:06:09
operator-self-healing	passed	00:08:23
pgvector-extension	passed	00:02:55
pitr	passed	00:12:00
scaling	passed	00:04:53
scheduled-backup	passed	00:31:39
self-healing	passed	00:08:41
sidecars	passed	00:02:36
start-from-backup	passed	00:11:49
tablespaces	passed	00:06:50
telemetry-transfer	passed	00:03:36
upgrade-consistency	passed	00:06:26
upgrade-minor	passed	00:05:15
users	passed	00:04:33

Summary	Value
Tests Run	24/24
Job Duration	01:34:49
Total Test Time	03:35:06

commit: 23ea0d5
image: perconalab/percona-postgresql-operator:PR-1384-23ea0d5c1