[UPGRADE] Upgrade of pgpool

[erzetpe]

Is your feature request related to a problem? Please describe.
We need to upgrade pgpool if possible and needed to the newer version. This task should be done after we will upgrade PostgreSQL to v13.

Describe the solution you'd like
We want to upgrade if possible and needed to the newer version of pgpool.

Describe alternatives you've considered
None.

Additional context
This task should be done after upgrade of PostgreSQL to v12.

---

DoD checklist

• Changelog updated
• COMPONENTS.md updated / doesn't need to be updated
• Feature has automated tests
• Automated tests passed (QA pipelines)
  • apply
  • upgrade
• Idempotency tested
• Documentation added / updated / doesn't need to be updated
• All conversations in PR resolved
• Solution meets requirements and is done according to design doc
• Usage compliant with license

[przemyslavic]

We are currently using bitnami/pgpool:4.1.1-debian-10-r29 image.
As for now the latest version is 4.2.2 (4.2.2-debian-10-r65).

[plirglo]

@przemyslavic i added small configuration change, shouldn't impact you tests: 65742d7

[przemyslavic]

After some time after deployment Pgpools pods crash on some clusters.

postgres-pool          pgpool-5478c5d8d4-clq2r                                             1/1     Running            0          18h
postgres-pool          pgpool-5478c5d8d4-pwt74                                             1/1     Running            0          18h
postgres-pool          pgpool-5478c5d8d4-qb969                                             0/1     CrashLoopBackOff   109        18h

Messages from different clusters on which the problem was reproduced:

    Last State:     Terminated
      Reason:       ContainerCannotRun
      Message:      OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:393: copying bootstrap data to pipe caused: write init-p: broken pipe: unknown

    Last State:     Terminated
      Reason:       ContainerCannotRun
      Message:      OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:545: container init caused: read init-p: connection reset by peer: unknown

    Last State:     Terminated
      Reason:       ContainerCannotRun
      Message:      OCI runtime create failed: container_linux.go:380: starting container process caused: container init was OOM-killed (memory limit too low?): unknown

[przemyslavic]

Fixed in #2545. After increasing the memory limit, the pods ran without crashing.
I checked the maximum memory usage after a few days and for RHEL/CentOS it was about 160 MB and for Ubuntu about 240 MB.
✔️ new deployments v4.2.4
✔️ upgrade from v4.1.1.