A previous commit removed the query knob
`internalChangeStreamUseTenantIdForTesting`. This was supposed to be a test-only knob for a feature that was never officially released. So the knob should not be in use in production anywhere.
However, fully removing a previously existing parameter/knob can have unintended side effects. So instead of removing the parameter entirely, this PR brings it back and marks it as deprecated. Using the parameter from now on will not have any effect other than logging a warning message about using a deprecated parameter.