Remove logging for "blocked" events

[ayushjain2809]

Also rectified docstring for "/blocked" endpoint

#37580 updated audit logs to exclude read-only events; but it also added logging "blocked" event which appears to be an oversight. I believe it was due to incorrect docstring for the "/blocked" endpoint.

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[hussein-awala]

Looks good, LGTM

[ayushjain2809]

Hi, can this be merged?
I believe the tests after @hussein-awala's approval failed due to reasons unrelated to this PR.

[potiuk]

Rebased to check.

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.