codeowners: update sql obs to cluster obs

[maryliag]

Update mentions of sql-observability to
cluster-observability.

Epic: none
Release note: None

[cockroach-teamcity]

This change is 

[maryliag]

bors r+

[craig]

Build succeeded:

• Bazel Essential CI (Cockroach)

[knz]

this probably needs a backport to the 23.1 branch, otherwise PRs against the 23.1 branch will be misattributed?

[maryliag]

blathers backport 23.1

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error setting reviewers, but backport branch blathers/backport-release-23.1-99691 is ready: POST https://api.github.com/repos/cockroachdb/cockroach/pulls/100441/requested_reviewers: 422 Reviews may only be requested from collaborators. One or more of the teams you specified is not a collaborator of the cockroachdb/cockroach repository. []

Backport to branch 23.1 failed. See errors above.

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