setIndexCommitQuorum command returns {ok: 1} when run against a mongos on a non-existent index build

(function() { "use strict" ;   const st = new ShardingTest({shards: 1 , mongos: 1 , rs: {nodes: 1 }});   const mongosDB = st.s0.getDB(jsTestName()); const mongosColl = mongosDB[jsTestName()];   assert .commandWorked(mongosColl.insert({_id: 1 }));   // Should not be OK. assert .commandWorked(mongosDB.runCommand( {setIndexCommitQuorum: jsTestName(), indexNames: [ "abcd" ], commitQuorum: 1 }));   // Mongos should fail with this error code too. let replTest = st.rs0; assert .commandFailedWithCode( replTest.getPrimary() .getDB(jsTestName()) .runCommand({setIndexCommitQuorum: jsTestName(), indexNames: [ "abcd" ], commitQuorum: 1 }), ErrorCodes.IndexNotFound);   st.stop(); }());