Updates sample cert and admin keystore

[DarshitChanpura]

Description

Downstream change coming from security plugin: https://github.com/opensearch-project/security/pull/4061

Check List

• [ ] New functionality includes testing.
  • [ ] All tests pass, including unit test, integration test and doctest
• [ ] New functionality has been documented.
  • [ ] New functionality has javadoc added
  • [ ] New functionality has user manual doc added
• [x] Commits are signed per the DCO using --signoff

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[DarshitChanpura]

should be merged post https://github.com/opensearch-project/security/pull/4061 is merged

[gaiksaya]

Hello reviewers,

This could be potential reason for failing tests with security atleast at the distribution level for 2.13.0. Please review and merge. Looks like it would need backport to 2.x and 2.13?

Thanks!