Baseline MAINTAINERS, CODEOWNERS, and external collaborator permissions

[dblock]

Follow opensearch-project/.github#125 to baseline MAINTAINERS, CODEOWNERS, and external collaborator permissions.

Close this issue when:

1. MAINTAINERS.md has the correct list of project maintainers.
2. CODEOWNERS exists and has the correct list of aliases.
3. Repo permissions only contain individual aliases as collaborators with maintain rights, admin, and triage teams.
4. All other teams are removed from repo permissions.

If this repo's permissions was already baselined, please confirm the above when closing this issue.

[ankitkala]

@dblock Regarding point 3 and 4 above, I don't think i have access for these

[ankitkala]

Closing now. Please reopen if anything is pending from our side.

[dblock]

Permissions are incorrect. You have 18 people with maintain access which doesn't match MAINTAINERS. Please work with @bbarani's team to remove the group that has maintain rights, and add individuals with maintain access.

[bbarani]

Baselined the maintainers and CODEOWNERS is green now. Closing this issue.

[dblock]

Verified, thx.