chore: use rootDir instead of includes in tsconfig

Fixes the type definitions generation on eslint-config-next by
setting the rootDir option, so it generates the .d.ts files in the
dist folder instead of dist/src.

Author: andreisena

packages/eslint-config-next/tsconfig.json

@@ -7,8 +7,8 @@
     "strict": true,
     "declaration": true,
     "resolveJsonModule": true,
-    "outDir": "dist"
+    "outDir": "dist",
+    "rootDir": "src"
   },
-  "include": ["src/**/*"],
   "exclude": ["node_modules", "dist"]
 }