This completely eliminates the Azure secret from the repo, following the below
guidance:
https://docs.github.com/en/actions/security-for-github-actions/security-hardening-your-deployments/configuring-openid-connect-in-azure
The federated identity is scoped to the `ci` environment, meaning:
* I had to specify this environment in some YAMLs. I don't believe there's any
downside to this.
* As previously, the CI works seamlessly both from PRs and in the manual
workflow.
I also deleted the tools/packaging/kata-deploy/action folder as it doesn't seem
to be used anymore, and it contains a reference to the secret.
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
9dd3807467