chore(package): update semantic-release to version 12.4.0

Closes #12

Author: greenkeeper[bot]

package.json

@@ -41,7 +41,7 @@
     "loopback-component-explorer": "4.2.0",
     "mocha": "3.4.2",
     "nyc": "11.0.2",
-    "semantic-release": "6.3.6",
+    "semantic-release": "12.4.0",
     "strong-error-handler": "2.1.0"
   },
   "config": {