Bump express-handlebars from 4.0.6 to 5.3.1

Bumps [express-handlebars](https://github.com/express-handlebars/express-handlebars) from 4.0.6 to 5.3.1.
- [Release notes](https://github.com/express-handlebars/express-handlebars/releases)
- [Changelog](https://github.com/express-handlebars/express-handlebars/blob/master/CHANGELOG.md)
- [Commits](https://github.com/express-handlebars/express-handlebars/compare/v4.0.6...v5.3.1)

---
updated-dependencies:
- dependency-name: express-handlebars
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -25,7 +25,7 @@
     "dotenv": "^6.1.0",
     "express": "^4.13.3",
     "express-graphql": "^0.6.12",
-    "express-handlebars": "^4.0.4",
+    "express-handlebars": "^5.3.1",
     "googleapis": "^39.1.0",
     "graphql": "^0.13.2",
     "morgan": "^1.8.0",