Bump ejs from 2.3.4 to 3.1.7 in /tests/dummy

Bumps [ejs](https://github.com/mde/ejs) from 2.3.4 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@v2.3.4...v3.1.7)

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

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

Author: dependabot[bot]

tests/dummy/package-lock.json

@@ -5,7 +5,7 @@
   "keywords": [],
   "dependencies": {
     "clone": "^1.0.2",
-    "ejs": "2.3.4",
+    "ejs": "3.1.7",
     "grunt": "1.3.0",
     "grunt-contrib-clean": "0.6.0",
     "grunt-contrib-coffee": "0.13.0",