feat: TLS support

[labrenbe]

Description

• Add TLS secret operator Volumes & VolumeMounts

Part of #61

Release Notes

Allow the configuration of TLS for the server (optional) and internal communication (mandatory) using SecretClasses:
https://docs.stackable.tech/home/stable/opensearch/usage-guide/security/#_tls

Definition of Done Checklist

• Not all of these items are applicable to all PRs, the author should update this template to only leave the boxes in that are relevant
• Please make sure all these things are done and tick the boxes

Author

• Changes are OpenShift compatible
• CRD changes approved
  - requestedSecretLifetime was already decided in decision: Make autoTls certificate lifetime configurable issues#673.
  - SecretClasses: Decision: TLS Support #69
• CRD documentation for all fields, following the style guide.
• Helm chart can be installed and deployed operator works
• Integration tests passed (for non trivial changes)
• Changes need to be "offline" compatible
• Links to generated (nightly) docs added
• Release note snippet added

Reviewer

• Code contains useful comments
• (Integration-)Test cases added
• Documentation added or updated. Follows the style guide.
• Changelog updated
• Cargo.toml only contains references to git tags (not specific commits or branches)

Acceptance

• Feature Tracker has been updated
• Proper release label has been added
• Links to generated (nightly) docs added
• Release note snippet added
• Add type/deprecation label & add to the deprecation schedule
• Add type/experimental label & add to the experimental features tracker

[siegfriedweber]

• The documentation is missing.
• A changelog entry is missing.
• If it should be possible to disable TLS on the HTTP port, then an integration test is required for this case.

[siegfriedweber]

LGTM

[lfrancke]

Please add release notes and if available a link to the docs for this.

[labrenbe]

I've added a release notes section to the issue.