refactor: use gts instead of xo

feat: add browser opening to test:notification
feat: add c8 and mocha for testing
feat: update Docker and ci
style: update editorconfig

test/functional/test-notification.ts

@@ -0,0 +1,38 @@
+import {Link, Store} from '../../src/store/model';
+import open from 'open';
+import {sendNotification} from '../../src/notification';
+import {config} from '../../src/config';
+
+const link: Link = {
+  brand: 'test:brand',
+  cartUrl: 'https://www.example.com/cartUrl',
+  model: 'test:model',
+  price: 100,
+  series: 'test:series',
+  url: 'https://www.example.com/url',
+};
+
+const store: Store = {
+  currency: '',
+  labels: {
+    inStock: {
+      container: 'test:container',
+      text: ['test:text'],
+    },
+  },
+  links: [link],
+  name: 'test:name',
+};
+
+/**
+ * Send test email.
+ */
+sendNotification(link, store);
+
+/**
+ * Open browser.
+ */
+if (config.browser.open) {
+  open(link.cartUrl ?? link.url);
+  open(link.url);
+}