Use new IPFS gateway for GET fetches

When adding the gateway URL, the wrapper will do a normal fetch to
`https://ipfs.kosmos.org/ipfs/$hash` instead of using the generic POST
requests to the IPFS API endpoint. This enables normal browser caching
for all IPFS documents in this app.

package.json

@@ -59,7 +59,7 @@
     "eslint-plugin-ember": "^5.2.0",
     "ethers": "^4.0.27",
     "kosmos-schemas": "^2.0.0",
-    "kredits-contracts": "^5.3.0",
+    "kredits-contracts": "^5.4.0",
     "loader.js": "^4.7.0",
     "qunit-dom": "^0.8.0",
     "tv4": "^1.3.0"