FluxCD: upgrade apiVersions for HelmRelease and HelmRepository

This MR bumps the apiVersion we use for HelmRelease and HelmRepository ; we couldn't do that before because we integrated Flux 2.3 after the release of Sylva 1.1.1, so we had to wait for having released Sylva 1.2 before changing them (bearing in mind that at the start of the upgrade to 1.2 we're still with the Flux version <2.3 that does not have those apiVersions).

This MR also fixes one heathCheck having the old apiVersion for a Kustomization.

This is important to avoid useless logs like:

{"level":"info","ts":"2024-12-04T15:17:13.975Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}
{"level":"info","ts":"2024-12-04T15:17:13.988Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}
{"level":"info","ts":"2024-12-04T15:17:14.007Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}
{"level":"info","ts":"2024-12-04T15:17:14.015Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}
{"level":"info","ts":"2024-12-04T15:17:14.030Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}
{"level":"info","ts":"2024-12-04T15:17:14.035Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}
{"level":"info","ts":"2024-12-04T15:17:14.039Z","logger":"runtime","msg":"v1beta2 HelmRepository is deprecated, upgrade to v1"}

that we have all over the place...