update handlebars to resolve npm vulnerabilities

Author: zahnster

package-lock.json

@@ -55,7 +55,7 @@
     "data.either": "1.5.1",
     "fs-extra": "5.0.0",
     "glob": "7.1.2",
-    "handlebars": "^4.1.2",
+    "handlebars": "^4.7.2",
     "handlebars-helpers": "0.10.0",
     "immutable": "3.8.2",
     "immutable-ext": "1.1.2",