Fix warning about webpack performance recommendations

[elharo]

[INFO] WARNING in asset size limit: The following asset(s) exceed the recommended size limit (244 KiB).
[INFO] This can impact web performance.
[INFO] Assets:
[INFO] dist/index.js (508 KiB)
[INFO] dist/query.js (596 KiB)
[INFO] dist/plan.js (558 KiB)
[INFO] dev/query_viewer.js (675 KiB)
[INFO] dist/embedded_plan.js (554 KiB)
[INFO] dist/stage.js (565 KiB)
[INFO] dist/worker.js (496 KiB)
[INFO] dist/timeline.js (486 KiB)
[INFO] dist/res_groups.js (496 KiB)
[INFO] dist/sql_client.js (720 KiB)
[INFO]
[INFO] WARNING in entrypoint size limit: The following entrypoint(s) combined asset size exceeds the recommended limit (244 KiB). This can impact web performance.
[INFO] Entrypoints:
[INFO] index (508 KiB)
[INFO] dist/index.js
[INFO] query (596 KiB)
[INFO] dist/query.js
[INFO] plan (558 KiB)
[INFO] dist/plan.js
[INFO] query_viewer (675 KiB)
[INFO] dev/query_viewer.js
[INFO] embedded_plan (554 KiB)
[INFO] dist/embedded_plan.js
[INFO] stage (565 KiB)
[INFO] dist/stage.js
[INFO] worker (496 KiB)
[INFO] dist/worker.js
[INFO] timeline (486 KiB)
[INFO] dist/timeline.js
[INFO] res_groups (496 KiB)
[INFO] dist/res_groups.js
[INFO] sql_client (720 KiB)
[INFO] dist/sql_client.js
[INFO]
[INFO] WARNING in webpack performance recommendations:
[INFO] You can limit the size of your bundles by using import() or require.ensure to lazy load some parts of your application.
[INFO] For more info visit https://webpack.js.org/guides/code-splitting/
[INFO]