issue-1242 Fixes issue that the subsequent listPage is not called because nothing subscribes to the Flux it returns.

Author: SaifuddinMerchant

integration-test/src/test/java/org/cloudfoundry/client/v3/SecurityGroupsTest.java

@@ -201,7 +201,8 @@ public void listStaging() {
     @Test
     public void listWithPagination() {
         this.securityGroup
-                .map(
+                .flux()
+                .flatMap(
                         securityGroup ->
                                 PaginationUtils.requestClientV3Resources(
                                         page ->