Extend express-graphql with test/audit suite

[sjparsons]

(when we're ready) @jaydenseric Adding this an issue as it's a better primitive for tracking

[spawnia]

There are many possibilities on how the test suite could be implemented, as has been discussed in the July 2022 working group meeting. I think it is time for someone to actually go through with an implementation, and thus believe this issue can be closed. @benjie @ghmcadams

[benjie]

I think it should remain open until there is a test suite

[michaelstaib]

@benjie can we close this as we now have a test suite and express is archived?

[spawnia]

For anyone who might find this issue later, the test/audit suite is developed at https://github.com/graphql/graphql-http.