Use a git secret based submodule repo to store secrets

[adiroiban]

we have this repo managed using git-secret https://github.com/twisted-infra/twisted-infra-secret

wolfwood was removed so we no longer have wolfwood.twistedmatrix.com:/git/buildbot-secrets

we should see how we can replace that plain-text repo with a GitHub private repo protected by git-secret

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maybe instead of cloning the secret's repo on the remote system, we can clone it on the local system, run git secret reveal and then push the plain text files using fabric over SSH.

[glyph]

That sounds good.

[adiroiban]

Amber has already push a change which is using the new private secret repo...and the change is now documented :)

I tried using git submodule, but git secret is not working with that