Add comment explaining next.config change

Author: joshwcomeau

next.config.js

@@ -36,7 +36,12 @@ const nextConfig = {
     // Don't bundle the shim unnecessarily.
     config.resolve.alias['use-sync-external-store/shim'] = 'react';
 
-    // TODO comment
+    // ESLint depends on the CommonJS version of esquery,
+    // but Webpack loads the ESM version by default. This
+    // alias ensures the correct version is used.
+    //
+    // More info:
+    // https://github.com/reactjs/react.dev/pull/8115
     config.resolve.alias['esquery'] = 'esquery/dist/esquery.min.js';
 
     const {IgnorePlugin, NormalModuleReplacementPlugin} = require('webpack');