Update dependency ejs to v3

Author: dev-mend-for-github-com[bot]

package.json

@@ -9,7 +9,7 @@
     "body-parser": "~1.13.2",
     "cookie-parser": "~1.3.5",
     "debug": "~2.2.0",
-    "ejs": "^2.4.2",
+    "ejs": "^3.1.10",
     "ejs-locals": "^1.0.2",
     "express": "~4.13.1",
     "express-session": "^1.13.0",