fix(main): SecretSyncController split namespaces

[aGallea]

What this PR does:
Splits WatchNamespaces when multiple namespaces provided (WATCH_NAMESPACE)

Which issue(s) this PR fixes:
Fixes #1399

Checklist

• Changes manually tested
• Automated Tests added/updated
• Documentation added/updated
• CHANGELOG.md updated (not required for documentation PRs)
• CLA Signed: DataStax CLA

[aGallea]

Initially opened this PR that caused the above 2 tests to fail:

unit/integration tests and build image / Run unit/integration tests
multi-cluster e2e tests / RemoveDcFromCluster
This seemed irrelevant to my changes, so I opened another PR with the same change to investigate further. However, this time, 3 different tests failed:

e2e tests / CreateSingleDseDatacenterCluster
e2e tests / CreateSingleHcdDatacenterCluster
e2e tests / PerNodeConfig/UserDefined

I'm looking for advice on how to proceed from here. Any guidance on how to debug or pinpoint the root cause would be appreciated.

[burmanm]

They were just flakes, I reran the tests.

[burmanm]

Any chance you could create CHANGELOG entry?

[aGallea]

Any chance you could create CHANGELOG entry?

Sure

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[burmanm]

I'll create a follow up ticket for proper warmup for cluster-scoped deployments.

[aGallea]

@burmanm Any chance you can rerun the failed checks please?

[burmanm]

Thanks for the PR.