[WIP][DNM] Save and apply release image signatures

[stbenjam]

openshift/oc#343 now requires you to do something about the eventual release image signatures. OpenShift CI is now failing:

+(./04_setup_ironic.sh:68): main(): oc adm release mirror --insecure=true -a combined-pullsecret--gyUsq8fVYL --from registry.svc.ci.openshift.org/ci-op-hmxpdxpw/release@sha256:7d9cc5731a84efab3c59fe66a81a66ec1d3e386183b383f905d0efc71dd6f161 --to-release-image virthost.ostest.test.metalkube.org:5000/localimages/local-release-image:7d9cc5731a84efab3c59fe66a81a66ec1d3e386183b383f905d0efc71dd6f161 --to virthost.ostest.test.metalkube.org:5000/localimages/local-release-image
error: if --to-dir and --apply-release-image-signature are not specified, --release-image-signature-to-dir must be used to specify a directory to export the signature

Unfortunately oc explodes when you give the release-image-signature-to-dir on older releases, so we again need to be aware of the oc version to give the option or not.

This whole change is problematic to deal with:

1. oc version --client -o json doesn't give you an easily machine comparable version
2. Even if we parse the releaseClientVersion, this isn't in 4.3 or 4.4 I think. The format from oc version has changed several times, and relying on it has broken us before
3. CI doesn't even tell us what OCP release we're using as everything is versioned as 0.0.1...

Will continue investigating on Monday. I filed https://bugzilla.redhat.com/show_bug.cgi?id=1825565 with a suggestion of exporting the config map to $PWD if no option is specified, instead of exploding.

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[stbenjam]

At some point we'll need to deal with release signatures, but oc is going to change to not require release-signature related options to preserve backwards compatibility. openshift/oc#392

/close

[openshift-ci-robot]

@stbenjam: Closed this PR.

In response to this:

At some point we'll need to deal with release signatures, but oc is going to change to not require release-signature related options to preserve backwards compatibility. openshift/oc#392

/close

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