WIP: Add additional storage configuration support for CRI-O

[saschagrunert]

- What I did

Implement MCO support for the AdditionalStorageConfig feature gate, adding three new ContainerRuntimeConfig fields:

• additionalLayerStores: configures extra read-only layer stores in storage.conf (additionallayerstores)
• additionalImageStores: configures extra read-only image stores in storage.conf (additionalimagestores)
• additionalArtifactStores: configures extra artifact stores via CRI-O drop-in (additional_artifact_stores)

All fields are gated behind the AdditionalStorageConfig feature gate (DevPreviewNoUpgrade/TechPreviewNoUpgrade).

E2E tests will follow in a separate PR.

Requires: openshift/api#2681
Refers to: openshift/enhancements#1934

- Description for the changelog
Added support for configuring additional layer, image, and artifact stores via ContainerRuntimeConfig, gated behind the AdditionalStorageConfig feature gate.

[openshift-ci]

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[openshift-ci]

@saschagrunert: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/verify-deps	d28f84f	link	true	/test verify-deps
ci/prow/e2e-hypershift	d28f84f	link	true	/test e2e-hypershift
ci/prow/e2e-gcp-op-ocl	d28f84f	link	false	/test e2e-gcp-op-ocl
ci/prow/e2e-aws-ovn	d28f84f	link	true	/test e2e-aws-ovn

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