chore: update dependency ejs to v4

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package-lock.json

@@ -42,7 +42,7 @@
     "@loopback/rest": "^15.0.1"
   },
   "dependencies": {
-    "ejs": "^3.1.10",
+    "ejs": "^4.0.1",
     "swagger-ui-dist": "5.31.0",
     "tslib": "^2.8.1"
   },