Relax max_seq_no_of_updates assertion in follow tests

If there's a failover on the follower, then its max_seq_no_of_updates is
bootstrapped from its max_seq_no which might be higher than the
max_seq_no_of_updates of the leader. We need to relax this check.

Relates #40249

Author: dnhatn

x-pack/plugin/ccr/src/test/java/org/elasticsearch/xpack/ccr/action/ShardFollowTaskReplicationTests.java

@@ -78,6 +78,7 @@
 import static java.util.Collections.emptyMap;
 import static java.util.Collections.emptySet;
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.greaterThanOrEqualTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.nullValue;
 
@@ -618,7 +619,8 @@ private void assertConsistentHistoryBetweenLeaderAndFollower(ReplicationGroup le
         }
         for (IndexShard followingShard : follower) {
             if (assertMaxSeqNoOfUpdatesOrDeletes) {
-                assertThat(followingShard.getMaxSeqNoOfUpdatesOrDeletes(), equalTo(leader.getPrimary().getMaxSeqNoOfUpdatesOrDeletes()));
+                assertThat(followingShard.getMaxSeqNoOfUpdatesOrDeletes(),
+                    greaterThanOrEqualTo(leader.getPrimary().getMaxSeqNoOfUpdatesOrDeletes()));
             }
             List<Tuple<String, Long>> docAndSeqNosOnFollower = getDocIdAndSeqNos(followingShard).stream()
                 .map(d -> Tuple.tuple(d.getId(), d.getSeqNo())).collect(Collectors.toList());