CLOUDP-323936 - re-add securityContext settings to HelmCharts

[MaciejKaras]

Summary

This PR re-introduces missing securityContext and podSecurityContext operator values that were previously available for MCO operator.

Resolves #168

Proof of Work

Passing new operator_security_context_test helmchart test.

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?
  • https://jira.mongodb.org/browse/DOCSP-54487
• 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.
• Helm Chart: Introduced two new helm fields operator.podSecurityContext and operator.securityContext that can be used to configure securityContext for Operator deployment through Helm Chart.

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.

[viveksinghggits]

LGTM, left a small comment on the RN.

[vinilage]

LGTM

[vinilage]

LGTM