fix: package.json & package-lock.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-VALIDATOR-13395830

Author: snyk-bot

package-lock.json

@@ -95,7 +95,7 @@
     "slugify": "^1.6.6",
     "sparkpost": "^2.1.4",
     "swagger-ui-express": "^5.0.0",
-    "validator": "^13.9.0",
+    "validator": "^13.15.20",
     "winston": "^3.10.0",
     "xmlbuilder2": "^3.1.1",
     "xss-clean": "^0.1.1"