ci: send slack message to channel after deploy (#7889)

tools/changelog/markdown.js

@@ -0,0 +1,25 @@
+import { jsxslack } from 'jsx-slack';
+import { marked, Renderer } from 'marked';
+
+export const render = markdown => {
+  const rendered = marked(markdown, {
+    renderer: new (class CustomRenderer extends Renderer {
+      heading({ tokens }) {
+        return `
+          <Fragment>
+            <Section><b>${tokens[0].text}</b></Section>
+            <Divider />
+          </Fragment>`;
+      }
+
+      list(token) {
+        return `<Section>${super.list(token)}</Section>`;
+      }
+
+      hr() {
+        return `<Divider />`;
+      }
+    })(),
+  });
+  return jsxslack([`<Blocks>${rendered}</Blocks>`]);
+};