Note: this failure was triaged in BF-44153 but is unrelated to the failure there. I have reached out to build barons to split out the BF ticket and will update the JIRA dependencies of this ticket once that happens

This fixes a failure in the plan_ranker_in_slow_query_logs.js that was caused due to an interaction between the
featureFlagGetExecutorDeferredEngineChoice and choice of CBR.

This only occurs on the enterprise-amazon-linux2-arm64-all-feature-flags-sbe-full variant where we explicitly set featureFlagGetExecutorDeferredEngineChoice to be false (default server FF value is true).

When this FF is set to false we use the regular SBE code path which, as far as I know, doesn't support CBR but the test is unaware of it.

Since we will eventually remove the regular SBE engine choice code path, the bandaid fix here is to just bail out of the test if the flag is disabled. We should remove this codeblock in SERVER-119581.