use prettier for the markdown formating

Author: cernicc

.vscode/extensions.json

@@ -10,5 +10,7 @@
         "ryanluker.vscode-coverage-gutters",
         // direnv, to use tool binaries from `nix` profile and set environment variables automatically
         "mkhl.direnv",
+        // Used for markdown formating
+        "esbenp.prettier-vscode"
     ]
-}
+}

.vscode/settings.default.json

@@ -15,6 +15,9 @@
   // Rust-analyzer doesn't need to build the wasm binary
   "rust-analyzer.cargo.extraEnv": {
     "SKIP_WASM_BUILD": "true"
+  },
+  "[markdown]": {
+    "editor.defaultFormatter": "esbenp.prettier-vscode"
   }
   // Recommended when developing benchmarks
   /*