Update dependency eslint-config-theme-next to v1.2.1

Author: renovate-bot

package.json

@@ -26,6 +26,6 @@
   },
   "devDependencies": {
     "eslint": "6.8.0",
-    "eslint-config-theme-next": "1.1.4"
+    "eslint-config-theme-next": "1.2.1"
   }
 }