K8SPG-681: Improve latest restorable time detection

[egegunes]

CHANGE DESCRIPTION

Previous command was incorrectly assuming that timestamp will be at the end of the line but while testing with sysbench we can see COMMIT lines like:

rmgr: Transaction len (rec/tot):    274/   274, tx:        779, lsn: 0/106234C0, prev 0/10623440, desc: COMMIT 2024-12-11 08:21:53.507524 UTC; inval msgs: catcache 55 catcache 54 catcache 7 catcache 6 catcache 32 catcache 55 catcache 54 catcache 55 catcache 54 relcache 16540 relcache 16526 snapshot 2608 relcache 16526 relcache 16540

This PR improves the command to support both above and simple lines like:

rmgr: Transaction len (rec/tot):    274/   274, tx:        779, lsn: 0/106234C0, prev 0/10623440, desc: COMMIT 2024-12-11 08:21:53.507524 UTC

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	Status
custom-extensions	passed
custom-tls	passed
demand-backup	passed
finalizers	passed
init-deploy	passed
monitoring	passed
one-pod	passed
operator-self-healing	passed
pitr	passed
scaling	passed
scheduled-backup	passed
self-healing	passed
start-from-backup	passed
tablespaces	passed
telemetry-transfer	passed
upgrade-consistency	passed
upgrade-minor	passed
users	passed
We run 18 out of 18

commit: c699b26
image: perconalab/percona-postgresql-operator:PR-978-c699b2658