fix: rename micro-frontends to microfrontends

There seems to be an internal issue with next.js, redirecting to `techradar/techradar/methods-and-patterns/micro-frontends/`

radar/2021-07-01/microfrontends.md

@@ -0,0 +1,11 @@
+---
+title:      "Micro Frontends"
+ring:       adopt
+quadrant:   methods-and-patterns
+tags: [architecture]
+---
+
+The Micro Frontends approach continues to prove to be a valuable pattern for large-scale systems developed by several teams.
+Therefore, we moved this pattern to "adopt".
+
+We use [page composing](methods-and-patterns/page-composing.html) as one implementation of this pattern.