Remove peerDep definition for vue-jest (#39)

Author: afontcu

package.json

@@ -66,7 +66,6 @@
   "main": "./lib/index.js",
   "peerDependencies": {
     "vue": "^2.5",
-    "vue-jest": "^4.0.0-beta.3",
     "vue-template-compiler": "^2.5"
   },
   "repository": {