chore(release): publish

- netlify-cms-app@2.15.57
 - netlify-cms-widget-markdown@2.14.4
 - netlify-cms@2.10.177

packages/netlify-cms-app/package.json

@@ -1,7 +1,7 @@
 {
   "name": "netlify-cms-app",
   "description": "An extensible, open source, Git-based, React CMS for static sites. Reusable congiuration with React as peer.",
-  "version": "2.15.56",
+  "version": "2.15.57",
   "homepage": "https://www.netlifycms.org",
   "repository": "https://github.com/netlify/netlify-cms/tree/master/packages/netlify-cms-app",
   "bugs": "https://github.com/netlify/netlify-cms/issues",
@@ -56,7 +56,7 @@
     "netlify-cms-widget-image": "^2.8.1",
     "netlify-cms-widget-list": "^2.10.1",
     "netlify-cms-widget-map": "^1.5.0",
-    "netlify-cms-widget-markdown": "^2.14.3",
+    "netlify-cms-widget-markdown": "^2.14.4",
     "netlify-cms-widget-number": "^2.5.0",
     "netlify-cms-widget-object": "^2.7.1",
     "netlify-cms-widget-relation": "^2.11.0",