Minimize error trace about internal ClassCircularityError in agent

Author: vsilaev

net.tascalate.javaflow.tools.javaagent/src/main/java/org/apache/commons/javaflow/instrumentation/JavaFlowClassTransformer.java

@@ -68,6 +68,9 @@ public byte[] call() {
 			} catch (final RuntimeException ex) {
 				log.error(ex);
 				return null;
+			} catch (ClassCircularityError ex) {
+			    log.warn("Ignoring class circularity error: " + ex.getMessage());
+			    return null;
 			} catch (final Error ex) {
 				log.error(ex);
 				throw ex;