MB-41915: Fix intermittent failure in eviction test

Occasionally the replica memory usage will be high enough/the amount of
memory that needs to be freed will be low enough that eviction does not
need to evict from active VBs in the

ActiveEvictedIfReplicaEvictionInsufficient

test. This test expects to evict from active vbuckets.

Change-Id: I001b462a30658b70307b6ed393afd342c0620903
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/138400
Tested-by: Build Bot <[email protected]>
Reviewed-by: Dave Rigby <[email protected]>

Author: jameseh96

engines/ep/tests/module_tests/item_pager_test.cc

@@ -1069,7 +1069,7 @@ TEST_P(STItemPagerTest, ActiveEvictedIfReplicaEvictionInsufficient) {
                 size_t pageableMem =
                         store->getVBucket(replicaVB)->getPageableMemUsage();
 
-                return pageableMem > watermarkDiff * 0.8;
+                return pageableMem > watermarkDiff * 0.7;
             });
     flushAndRemoveCheckpoints(replicaVB);