Bump ejs from 2.5.9 to 3.1.7

Bumps [ejs](https://github.com/mde/ejs) from 2.5.9 to 3.1.7.
- [Release notes](https://github.com/mde/ejs/releases)
- [Changelog](https://github.com/mde/ejs/blob/main/CHANGELOG.md)
- [Commits](mde/ejs@v2.5.9...v3.1.7)

---
updated-dependencies:
- dependency-name: ejs
  dependency-type: direct:production
...

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

Author: dependabot[bot]

package-lock.json

@@ -10,7 +10,7 @@
     "bootstrap": "^3.3.7",
     "cookie-parser": "~1.4.3",
     "debug": "~2.6.3",
-    "ejs": "~2.5.6",
+    "ejs": "~3.1.7",
     "express": "^4.17.1",
     "mongoose": "^5.6.0",
     "morgan": "^1.9.1",