DEV: Update linting (#3)

.eslintrc

-{
-  "extends": "eslint-config-discourse",
-  "globals": {
-    "settings": "readonly",
-    "themePrefix": "readonly"
-  }
-}

.eslintrc.cjs

+module.exports = require("@discourse/lint-configs/eslint-theme");

.github/workflows/discourse-theme.yml

+name: Discourse Theme
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  ci:
+    uses: discourse/.github/.github/workflows/discourse-theme.yml@v1

.prettierrc.cjs

+module.exports = require("@discourse/lint-configs/prettier");

.template-lintrc.cjs

+module.exports = require("@discourse/lint-configs/template-lint");

.template-lintrc.js

-module.exports = {
-  plugins: ["ember-template-lint-plugin-discourse"],
-  extends: "discourse:recommended",
-};

package.json

 {
-  "author": "joffreyjaffeux",
-  "license": "MIT",
+  "private": true,
   "devDependencies": {
-    "eslint-config-discourse": "latest"
+    "@discourse/lint-configs": "1.3.9",
+    "ember-template-lint": "6.0.0",
+    "eslint": "8.57.0",
+    "prettier": "2.8.8"
   }
 }