Remove support for legacy user-provided service instance credentials

[danail-branekov]

In 0.12.0 we introduced support for objects in user-provided services credentials (https://github.com/cloudfoundry/korifi/issues/2900). When we have been working on that, we wanted to avoid workloads restart on korifi upgrade in order to ensure smooth upgrade path, and came up with some legacy support code.

With the upcoming release the smooth upgrade is not going to be possible as workloads have to restart, see

• https://github.com/cloudfoundry/korifi/issues/3410
• https://github.com/cloudfoundry/korifi/pull/3483

As there is no way around that, let's make use of it and get rid of the legacy secret format support:

• https://github.com/cloudfoundry/korifi/blob/f9b24a36a90e5d614e2fa5abc243ae7dd2c87ace/controllers/controllers/services/instances/upsi/controller.go#L151-L183

• https://github.com/cloudfoundry/korifi/blob/f9b24a36a90e5d614e2fa5abc243ae7dd2c87ace/controllers/controllers/services/bindings/upsi/controller.go#L90-L106

• [x] Ensure that user provided services that have been created with 0.12.0 are fine

• [ ] Ensure upsis created with 0.11.0 and reconciled by 0.12.0 are fine

• [ ] Check the behaviour of bumping 0.11.0 straigh into the release candidate. If broken, make sure not to forget to document that 0.12.0 is a prerequisite for this release.

[danail-branekov]

Turns out that maybe this would not that trivial :(

Imagine the following scenario:

• UPSI created with 0.11.0. The credentials secret referenced by the UPSI is in the old format

• Korifi bumped to 0.12.0

  • As a result of the bump, the CFServiceInstance.Spec.SecretName resource still references the initial secret (in the old format)
  • However, as a result of the migration, its CFServiceInstance.Status.Credentials.Name is set to the migrated secret with the -migrated suffix). this migrated secret is in the new format
  • NOTE that the service instance spec is not changed at this point

• Now Korifi is bumped to the release candidate

  • The upsi controller reconciles the CFServiceInstance. It now no longer has the knowledge that this might be a pre 0.12.0 upsi, therefore jumps straight into validating the secret referenced by CFServiceInstance.Spec.SecretName. As that secret is in the old format (see above), validation fails

I have not tested yet, but I am pretty sure we would see the same error if we jump from 0.11.0 to the release candidate