Fix linting issues

assets/javascripts/discourse/components/solved-unaccept-answer-button.gjs

@@ -3,7 +3,7 @@ import { tracked } from "@glimmer/tracking";
 import { action } from "@ember/object";
 import { service } from "@ember/service";
 import { htmlSafe } from "@ember/template";
-import { and, not } from "truth-helpers";
+import { and } from "truth-helpers";
 import DButton from "discourse/components/d-button";
 import icon from "discourse/helpers/d-icon";
 import { ajax } from "discourse/lib/ajax";

assets/javascripts/discourse/initializers/extend-for-solved-button.gjs

@@ -136,7 +136,7 @@ function customizePostMenu(api) {
 }
 
 function handleMessages(api) {
-  const handleMessages = async (controller, message) => {
+  const callback = async (controller, message) => {
     const topic = controller.model;
 
     if (topic) {
@@ -144,8 +144,8 @@ function handleMessages(api) {
     }
   };
 
-  api.registerCustomPostMessageCallback("accepted_solution", handleMessages);
-  api.registerCustomPostMessageCallback("unaccepted_solution", handleMessages);
+  api.registerCustomPostMessageCallback("accepted_solution", callback);
+  api.registerCustomPostMessageCallback("unaccepted_solution", callback);
 }
 
 export default {