Migrate from express-graphql to graphql-http

Hello.
I'm getting this warning on `npm i`
```
npm WARN deprecated express-graphql@0.12.0: This package is no longer maintained. We recommend using `graphql-http` instead. Please consult the migration document https://github.com/graphql/graphql-http#migrating-express-grpahql.
```
Is it nessecary/possible to update this dependency?
Thank you.

Start with the package dependency on express-graphql and read the graphql-http migration document linked in the issue. Determine the Koa integration points affected by the migration, then verify that the package installs without the deprecation warning and that its GraphQL HTTP behavior remains covered by the existing checks.

Written by the indexing model from the issue text.