Fix symbol extraction for interface static method (#9597)

not all methods with code  in interface are default, only the
non-static ones

Author: jpbempel

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

@@ -237,8 +237,10 @@ private static Collection<String> extractMethodModifiers(
               "Invalid access modifiers method[" + methodNode.name + methodNode.desc + "]: " + bit);
       }
     }
-    // if class is an interface && method as code this is a default method
-    if ((classNode.access & Opcodes.ACC_INTERFACE) > 0 && methodNode.instructions.size() > 0) {
+    // if class is an interface && method has code && non-static this is a default method
+    if ((classNode.access & Opcodes.ACC_INTERFACE) > 0
+        && methodNode.instructions.size() > 0
+        && (methodNode.access & Opcodes.ACC_STATIC) == 0) {
       results.add("default");
     }
     return results;

dd-java-agent/agent-debugger/src/test/java/com/datadog/debugger/symbol/SymbolExtractionTransformerTest.java

@@ -829,6 +829,14 @@ public void symbolExtraction14() throws IOException, URISyntaxException {
         null,
         null,
         Void.TYPE.getTypeName());
+    Scope m4MethodScope = i1ClassScope.getScopes().get(1);
+    assertLangSpecifics(
+        m4MethodScope.getLanguageSpecifics(),
+        asList("public", "static"),
+        null,
+        null,
+        null,
+        String.class.getTypeName());
     Scope myEnumClassScope = symbolSinkMock.jarScopes.get(3).getScopes().get(0);
     assertLangSpecifics(
         myEnumClassScope.getLanguageSpecifics(),

dd-java-agent/agent-debugger/src/test/resources/com/datadog/debugger/symboltest/SymbolExtraction14.java

@@ -23,6 +23,9 @@ private strictfp synchronized final String m2(String... strVarArgs) {
 
 interface I1 {
   default void m3(){}
+  static String m4(String arg){
+    return arg;
+  }
 }
 
 interface I2 {