Bump ejs from 2.6.2 to 3.1.7

Bumps [ejs](https://github.com/mde/ejs) from 2.6.2 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@v2.6.2...v3.1.7)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -8,7 +8,7 @@
     "cookie-parser": "^1.4.4",
     "d3": "^5.16.0",
     "dotenv": "^7.0.0",
-    "ejs": "^2.6.2",
+    "ejs": "^3.1.7",
     "express": "^4.16.4",
     "express-fileupload": "^1.1.4",
     "express-session": "^1.16.2",