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

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-BRACEEXPANSION-9789073

package.json

@@ -34,10 +34,10 @@
     "morgan": "^1.10.0",
     "nodemailer": "^6.6.1",
     "npm-watch": "^0.11.0",
-    "postcss-cli": "^11.0.1",
+    "postcss-cli": "^8.3.1",
     "pug": "^3.0.2",
     "tailwind-hamburgers": "^1.1.1",
-    "tailwindcss": "^2.2.15",
+    "tailwindcss": "^3.0.0",
     "winston": "^3.3.3"
   },
   "devDependencies": {