Upgrade: Update semantic-release to version 15.12.4

Author: markusguenther

package.json

@@ -51,7 +51,7 @@
     "react": "^16.6.3",
     "react-dom": "^16.6.3",
     "rimraf": "^2.6.2",
-    "semantic-release": "^15.12.0",
+    "semantic-release": "^15.12.4",
     "sinon": "^7.1.1",
     "travis-deploy-once": "^5.0.9"
   },

yarn.lock

@@ -7828,7 +7828,7 @@ scheduler@^0.11.2:
     loose-envify "^1.1.0"
     object-assign "^4.1.1"
 
-semantic-release@^15.12.0:
+semantic-release@^15.12.4:
   version "15.12.4"
   resolved "https://registry.yarnpkg.com/semantic-release/-/semantic-release-15.12.4.tgz#d0f4c3649d01e2e29a9df5e4886bab869d75ef02"
   integrity sha512-po30Te9E26v3Qb/G9pXFO6lCTFO07zvliqH00vmfuCoAjl1Wpg9SKb9dXVFM7BTdg5Fr/KqbdOsqHkT7kR4FeQ==