Adds bootstrap data secret

[Sadzeih]

This PR adds the ability to add a secret to be able to add custom certs or scripts during the bootstrap job.

For example you can add federated roots.

[Sadzeih]

Ultimately, I think adding a way to add federated roots post-boostrap would be great because currently there's no way to do that.

[maraino]

Hi @Sadzeih, thanks for your contribution, I can merge this, but I think the name ca.bootstrap.data is quite confusing, perhaps changing the name to something with the word secret will be more appropriate.

[CLAassistant]

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