chore: update multiformats (#160)

Let's force update multiformats. Well, I know in theory this is not needed but skypack does not do a good job with getting latest releases sometimes: https://codepen.io/vascosantos/pen/abWWbJe?editors=0011

![image](https://user-images.githubusercontent.com/7295071/125923376-15dcbbca-1d09-4199-abd6-48143ffa8752.png)

Currently this module does not work in skypack, but I would like to see if multiformats/js-multiformats#105 also fixes it.

Co-authored-by: Alex Potsides <alex@achingbrain.net>

Author: vasco-santos

packages/ipfs-unixfs-exporter/package.json

@@ -63,9 +63,9 @@
     "interface-blockstore": "^1.0.0",
     "ipfs-unixfs": "^5.0.0",
     "it-last": "^1.0.5",
-    "multiformats": "^9.0.4",
+    "multiformats": "^9.4.2",
     "murmurhash3js-revisited": "^3.0.0",
-    "uint8arrays": "^2.1.5"
+    "uint8arrays": "^2.1.7"
   },
   "types": "dist/src/index.d.ts",
   "files": [

packages/ipfs-unixfs-importer/package.json

@@ -57,10 +57,10 @@
     "it-first": "^1.0.6",
     "it-parallel-batch": "^1.0.9",
     "merge-options": "^3.0.4",
-    "multiformats": "^9.0.4",
+    "multiformats": "^9.4.2",
     "murmurhash3js-revisited": "^3.0.0",
     "rabin-wasm": "^0.1.4",
-    "uint8arrays": "^2.1.2"
+    "uint8arrays": "^2.1.7"
   },
   "types": "dist/src/index.d.ts",
   "files": [