feat: add dependency for Eta

Author: exoup

package.json

@@ -27,6 +27,7 @@
     "ejs": "^3.1.9",
     "eslint": "8.42.0",
     "eslint-config-xo-lass": "2",
+    "eta": "^3.1.1",
     "fixpack": "^4.0.0",
     "haml-coffee": "^1.14.1",
     "hamlet": "^0.3.3",