Update Postgres DB to v. 16

[NicolasLivanos]

Describe the task We need to update our Postgres DB - we're now 2 major versions behind. First upgrade to postgres 15, then to postgres 16. Also, our current version of postGIS is 3.2, which is supported (don't need to update it twice)

Acceptance Criteria

• [ ] Postgres prod is running version 15
• [ ] Then postgres Prod is running version 16
• [ ] Thoroughly document this process + present to DDS (Lightning Talk)

Additional Context

• Start task after operator update: https://chat.developer.gov.bc.ca/channel/crunchydb?msg=hWCTbMbtoH5eSs8z6
• Crunchy is no longer publishing images for postgres14:

• RC thread: https://chat.developer.gov.bc.ca/channel/crunchydb?msg=CnEfe5wSXXY7TcMT6
• Create + save a copy of our PROD db in TEST for testing the upgrade
• Request for Temporary Upgrade of Storage Space in PROD
• May need to migrate from public schema to more specific one(s): https://www.crunchydata.com/blog/be-ready-public-schema-changes-in-postgres-15
• https://access.crunchydata.com/documentation/postgres-operator/latest/releases/5.5.x

[NicolasLivanos]

Hey team! Please add your planning poker estimate with Zenhub @andrea-williams @conbrad

[dgboss]

PGUpgrade does not support upgrading a postgis cluster. The crunchy-upgrade container image also does not support upgrading a postgis cluster. We might be stuck with a pg_dump from the v14 cluster and a pg_restore into a new v15 cluster. This requires some downtime so would need to be done outside of fire season.

Putting this on the back burner for now.

[conbrad]

FYI: https://chat.developer.gov.bc.ca/channel/crunchydb?msg=jJv6x47Bh92FwXfxv