[Backport 2.5] Update default setting for integ tests (#106)

Updates defaul ml commons setting
"plugins.ml_commons.only_run_on_ml_node" to false. This prevents
integration tests from failing when an ml node is not explicitly added.

Also, make circuit breaker 100 for tests

Signed-off-by: John Mazanec <jmazane@amazon.com>

src/test/java/org/opensearch/neuralsearch/common/BaseNeuralSearchIT.java

@@ -30,6 +30,7 @@
 import org.apache.http.entity.StringEntity;
 import org.apache.http.message.BasicHeader;
 import org.apache.http.util.EntityUtils;
+import org.junit.Before;
 import org.opensearch.client.Request;
 import org.opensearch.client.RequestOptions;
 import org.opensearch.client.Response;
@@ -58,6 +59,32 @@ public abstract class BaseNeuralSearchIT extends OpenSearchSecureRestTestCase {
 
     protected final ClassLoader classLoader = this.getClass().getClassLoader();
 
+    @Before
+    public void setupSettings() {
+        updateClusterSettings("plugins.ml_commons.only_run_on_ml_node", false);
+        updateClusterSettings("plugins.ml_commons.native_memory_threshold", 100);
+    }
+
+    @SneakyThrows
+    protected void updateClusterSettings(String settingKey, Object value) {
+        XContentBuilder builder = XContentFactory.jsonBuilder()
+            .startObject()
+            .startObject("persistent")
+            .field(settingKey, value)
+            .endObject()
+            .endObject();
+        Response response = makeRequest(
+            client(),
+            "PUT",
+            "_cluster/settings",
+            null,
+            toHttpEntity(Strings.toString(builder)),
+            ImmutableList.of(new BasicHeader(HttpHeaders.USER_AGENT, ""))
+        );
+
+        assertEquals(RestStatus.OK, RestStatus.fromCode(response.getStatusLine().getStatusCode()));
+    }
+
     protected String uploadModel(String requestBody) throws Exception {
         Response uploadResponse = makeRequest(
             client(),