Updated docs to reflect express-graphql deprecation

[pTinosq]

Description

I wanted to follow the tutorial on Running an Express GraphQL Server on the official graphql.org website and found that the express-graphql library has been deprecated and replaced with the graphql-http library.

It would be nice to see an updated version of this tutorial created by the GraphQL foundation. (specifically for Express.js)

Steps to Reproduce

Head over to https://graphql.org/graphql-js/running-an-express-graphql-server and the whole tutorial uses the deprecated express-graphql library

Expected Result

A tutorial on how to quickly get up and running on express.js with the graphql-http library.

Actual Result

An outdated tutorial that uses a deprecated library.

Additional Context

The GraphQL Foundation adopts graphql-http blog post was written over a year ago and the tutorial is yet to be updated!

[benjie]

@enisdenjo Maybe one of your existing examples would be straightforward to port over?

[enisdenjo]

Check out #1616!

[pTinosq]

Fantastic stuff... thanks for this!