Enable Apollo-Client in browser extension background script

Created by: valerybugakov

Context

Apollo-Client is not configured yet to execute requests in the background script. We fallback to requestGraphQLInBackground when client.watchQuery is called.

A follow-up for the PR that enabled Apollo-Client for extensions query.

Changes required

We need to implement a bridge similar to background.requestGraphQL or update browser extension integration tests to allow fetching data in the main thread.