Remove actions unavailable in OM from search external mongod test

[anandsyncs]

Summary

This pull request makes targeted adjustments to the set of permitted actions in the community-replicaset-sample-mflix-external.yaml Kubernetes fixture. The main change is the removal of several search index-related actions from the permissions list.

Permissions cleanup:

• Removed the following actions from the allowed list: listSearchIndexes, createSearchIndexes, dropSearchIndex, and updateSearchIndex
• Removed cleanupStructuredEncryptionData

Proof of Work

Tests pass

Checklist

• Have you linked a jira ticket and/or is the ticket in the title?
• Have you checked whether your jira ticket required DOCSP changes?
• Have you added changelog file?
  • use skip-changelog label if not needed
  • refer to Changelog files and Release Notes section in CONTRIBUTING.md for more details

[github-actions]

⚠️ (this preview might not be accurate if the PR is not rebased on current master branch)

MCK 1.5.0 Release Notes

New Features

• Improve automation agent certificate rotation: the agent now restarts automatically when its certificate is renewed, ensuring smooth operation without manual intervention and allowing seamless certificate updates without requiring manual Pod restarts.

Bug Fixes

• MongoDBMultiCluster: fix resource stuck in Pending state if any clusterSpecList item has 0 members. After the fix, a value of 0 members is handled correctly, similarly to how it's done in the MongoDB resource.

[lucian-tosa]

Could you add a reason for this change in the description? The role created by the operator still has those privileges