refactor: Remove chai and dirty chai from dev dependencies (#88)

Looks like the tests that used chai got moved out to seperate modules in 
andrew@1100ff6#diff-3dcfe508eca97a681a25f38300c9d678

Author: andrew

package.json

@@ -53,8 +53,6 @@
   },
   "devDependencies": {
     "aegir": "^18.0.3",
-    "chai": "^4.1.2",
-    "dirty-chai": "^2.0.1",
     "go-ipfs-dep": "~0.4.17",
     "mock-require": "^3.0.2",
     "npm-run-all": "^4.1.3",