small refactor for diagram rest api test calss (#220)

Signed-off-by: Tihomir Surdilovic <[email protected]>

Author: tsurdilo

diagram-rest/src/test/java/io/serverlessworkflow/diagramrest/ServerlesRequestHelperTest.java renamed to diagram-rest/src/test/java/io/serverlessworkflow/diagramrest/DiagramGenerationTest.java

@@ -33,7 +33,7 @@
         DiagramRequestHelper.class
 })
 @WebFluxTest
-class ServerlesRequestHelperTest {
+class DiagramGenerationTest {
 
     private DiagramRequestHelper serverlesRequestHelper;