FsyncLock interferes with RSTL acquisition during stepdown. This makes tests which run fsyncLock incompatible with stepdowns. There is also an additional issue caused by SERVER-133098 in sharded clusters with CSRS stepdowns and fsyncLock, but even if that issue were fixed thus allowing another node to step up and run fsyncUnlock, the fsyncUnlock command must run against shard primaries and so this test would leave the initial primary still fscynLocked and trying to step down.

Adding the requires_fsync tag to the exclusion list in sharding_csrs_continuous_config_stepdown will prevent us from seeing these issues again in the future.