Fixing org.opensearch.monitor.os.OsProbeTests::testLogWarnCpuMessageOnlyOnes when CGroups are not available (#2101)

Signed-off-by: Andriy Redko <[email protected]>
(cherry picked from commit a942b27)

Author: reta

server/src/test/java/org/opensearch/monitor/os/OsProbeTests.java

@@ -41,6 +41,7 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.lessThanOrEqualTo;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.Assume.assumeThat;
 
 import java.io.IOException;
 import java.math.BigInteger;
@@ -295,6 +296,7 @@ List<String> readSysFsCgroupCpuAcctCpuStat(String controlGroup) throws IOExcepti
             }
         };
 
+        assumeThat("CGroups are not available", noCpuStatsOsProbe.areCgroupStatsAvailable(), is(true));
         noCpuStatsOsProbe.osStats();
         // no nr_throttled and throttled_time
         verify(logger, times(2)).warn(anyString());