Avoid throwing exception for invalid modifiers (#10458)

OpenJ9 is behaving weirdly for access modifiers

Author: jpbempel

dd-java-agent/agent-debugger/src/main/java/com/datadog/debugger/symbol/SymbolExtractor.java

@@ -195,7 +195,7 @@ private static Collection<String> extractClassModifiers(int access) {
           results.add("deprecated");
           break;
         default:
-          throw new IllegalArgumentException("Invalid access modifiers: " + bit);
+          LOGGER.debug("Invalid class access modifiers: {}", bit);
       }
     }
     return results;
@@ -250,8 +250,11 @@ private static Collection<String> extractMethodModifiers(
           results.add("deprecated");
           break;
         default:
-          throw new IllegalArgumentException(
-              "Invalid access modifiers method[" + methodNode.name + methodNode.desc + "]: " + bit);
+          LOGGER.debug(
+              "Invalid access modifiers method[{}::{}]: {}",
+              classNode.name,
+              methodNode.name + methodNode.desc,
+              bit);
       }
     }
     // if class is an interface && method has code && non-static this is a default method
@@ -302,7 +305,7 @@ private static Collection<String> extractFieldModifiers(int access) {
           results.add("deprecated");
           break;
         default:
-          throw new IllegalArgumentException("Invalid access modifiers: " + bit);
+          LOGGER.debug("Invalid access modifiers: {}", bit);
       }
     }
     return results;