[`firestartr-bootstrap`] Update bootstrap process to include new `ExternalSecrets` state repository

[juanjosevazquezgil]

Motivation

We want to separate the ExternalSecret CRs into their own state repository, by default named state-secrets, instead of sharing state-infra with TerraformWorkspaces. To achieve this, we want to update this module so it creates this repo by default (by adding it to the example Bootstrap.yaml configuration file) and also uploads all created ExternalSecrets to it.

Acceptance criteria

• The process creates the new repository
• The process pushes ExternalSecrets to the new repository
• The documentation has been updated