cleanup(ci): Delete unused cached state patch job

[teor2345]

Motivation

The cached state isn't used for Docker unit tests, so its patch job isn't needed.

There is no corresponding job in the Docker unit tests:
https://github.com/ZcashFoundation/zebra/blob/main/.github/workflows/ci-unit-tests-docker.yml#L78

The job and patch are correctly configured in the Docker GCP integration tests:
https://github.com/ZcashFoundation/zebra/blob/main/.github/workflows/ci-integration-tests-gcp.yml#L105
https://github.com/ZcashFoundation/zebra/blob/main/.github/workflows/ci-integration-tests-gcp.patch.yml#L30

PR Author Checklist

Check before marking the PR as ready for review:

• Will the PR name make sense to users?
• Does the PR have a priority label?
• Have you added or updated tests?
• Is the documentation up to date?

Not a significant change.

If a checkbox isn't relevant to the PR, mark it as done.

Solution

Delete the unused duplicate patch job.

Testing

If CI passes we're fine here.

Review

This is a low priority cleanup. It can merge at any time during the release process, because it doesn't need to go in the changelog.

Reviewer Checklist

Check before approving the PR:

• Does the PR scope match the ticket?
• Are there enough tests to make sure it works? Do the tests cover the PR motivation?
• Are all the PR blockers dealt with?
  PR blockers can be dealt with in new tickets or PRs.

And check the PR Author checklist is complete.

[teor2345]

This PR can merge at any time during the release process, because it doesn't need to go in the changelog.

[gustavovalverde]

LGTM