qa/standalone/scrub: fix TEST_periodic_scrub_replicated

A bogus change introduced as part of PR#54363 (commit
fbb7d73) changed multiple 'scrub' commands to 'scheduled-scrub'.
In this one instance - that was wrong.

Fixes: https://tracker.ceph.com/issues/69276

Signed-off-by: Ronen Friedman <[email protected]>

Author: ronen-fr

qa/standalone/scrub/osd-scrub-repair.sh

@@ -5833,7 +5833,7 @@ function TEST_periodic_scrub_replicated() {
 
     flush_pg_stats
     # Request a regular scrub and it will be done
-    pg_schedule_scrub $pg
+    pg_scrub $pg
     grep -q "Regular scrub request, deep-scrub details will be lost" $dir/osd.${primary}.log || return 1
 
     # deep-scrub error is no longer present