add type check in the equal method (#11346)

Author: wing328

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaPlayFrameworkCodegen.java

@@ -451,6 +451,14 @@ public CodegenSecurity filterByScopeNames(List<String> filterScopes) {
 
         @Override
         public boolean equals(Object o) {
+            if (o == null) {
+                return false;
+            }
+
+            if (this.getClass() != o.getClass()) {
+                return false;
+            }
+
             boolean result = super.equals(o);
             JavaPlayFrameworkCodegen.ExtendedCodegenSecurity that = (JavaPlayFrameworkCodegen.ExtendedCodegenSecurity) o;
             return result &&