[`@embroider/router`] url query params are not sticky

[andrew-paterson]

Clone https://github.com/andrew-paterson/sticky-params-bug

Run pnpm install and pnpm start.

Use the nav menu to go to my-route. Use the input to update the name query param- it will update in the page URL.

Then use the nav menu to navigate to index and then back to my-route.

The name QP is gone.

Note that if you switch to the Ember router in app/router.js and repeat the above steps, the name QP is sticky, and is retained after navigating away and back again.