K8SPG-818 Update versions for 2.7.0 release

[jvpasinatto]

CHANGE DESCRIPTION

Problem:
Short explanation of the problem.

Cause:
Short explanation of the root cause of the issue if applicable.

Solution:
Short explanation of the solution we are providing with this PR.

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	00:06:39
custom-extensions	passed	00:08:37
custom-tls	passed	00:04:56
demand-backup	passed	00:24:52
finalizers	passed	00:03:38
init-deploy	passed	00:03:11
monitoring	passed	00:07:08
monitoring-pmm3	passed	00:07:39
one-pod	passed	00:05:37
operator-self-healing	passed	00:07:57
pitr	passed	00:12:07
scaling	passed	00:04:42
scheduled-backup	passed	00:25:37
self-healing	passed	00:08:47
sidecars	passed	00:02:26
start-from-backup	passed	00:12:43
tablespaces	passed	00:07:49
telemetry-transfer	passed	00:03:11
upgrade-consistency	passed	00:05:39
upgrade-minor	passed	00:04:36
users	passed	00:04:58
We run 21 out of 21		02:53:00

commit: 9473b3e
image: perconalab/percona-postgresql-operator:PR-1213-9473b3ee6