Add Sealed Secret private and public key to maintenance download values

[ElderMatt]

WHY

When I want to recreate my Otomi instance with download the values.yaml from the maintenance page, I would like to have an option to download the values yaml which includes the disaster recovery keys from Sealed Secrets.

User Story

AS A Admin

I WANT TO have an option to download the values.yaml with Sealed Secret recovery keys

SO That I can re-create my Otomi instance and re-use my Sealed Secrets

Acceptance criteria

GIVEN Maintenance page with values.yaml download WHEN I click a option to include the Sealed Secrets recovery keys THEN I can download the values.yaml with the Sealed Secrets recovery keys in it.

Definition of done

• [ ] Relevant PRs are merged
• [ ] Tested by peer
• [ ] Updated documentation reviewed by peer
• [ ] Short demo video recorded and stored on google drive (if applicable)