It resilience (#1600)

* do not fail the whole test if the curl command returns a non-zero status

we expect if to fail, and want to retry it until it is successful.  it
can fail because the web app has not had time to start up yet.  the
current code throws a runtime exception on a non-zero return code, which
causes this test to fail too fast and incorrectly.

* use vanaja's simpler solution

* fix code so it retries and does not die on RuntimeException on first
iteration.

Observed a failure in this run:
https://build.weblogick8s.org:8443/job/weblogic-kubernetes-operator-quicktest/1375/testReport/oracle.kubernetes.operator/ItElasticLogging/testWebLogicLogSearch/

testWebLogicLogSearch fails arund line 1114 of the log (out file).
The first fall to execSearchQuery is getting rc=6 from the curl
command and then throws an RE and prematurely aborts the test.

This PR changes it to use ExecCommand.exec() instead of TestUtils.exec()
so that the result is just returned to the called without killing
the test run.

Author: markxnelson

integration-tests/src/test/java/oracle/kubernetes/operator/ItElasticLogging.java

@@ -14,6 +14,7 @@
 import java.util.regex.Pattern;
 
 import oracle.kubernetes.operator.utils.Domain;
+import oracle.kubernetes.operator.utils.ExecCommand;
 import oracle.kubernetes.operator.utils.ExecResult;
 import oracle.kubernetes.operator.utils.LoggerHelper;
 import oracle.kubernetes.operator.utils.Operator;
@@ -514,7 +515,7 @@ private String execSearchQuery(String queryCriteria, String index)
             .append("'")
             .toString();
     LoggerHelper.getLocal().log(Level.INFO, "Command to search: " + cmd);
-    ExecResult result = TestUtils.exec(cmd);
+    ExecResult result = ExecCommand.exec(cmd);
 
     return result.stdout();
   }