Improvement to optional spec-compliant

[d-exclaimation]

Is your feature request related to a problem? Please describe.
It would be great if Pioneer can pass some if not most of the optional spec requirement for GraphQL over HTTP.

Describe the solution you'd like
The changes shouldn't break any existing behaviour of Pioneer and shouldn't require anything done from the user side.

Describe alternatives you've considered
We are slightly at the same compliant as Apollo Server which is technically is enough, but if the optional requirements aren't causing any issues, it should be fine to implement it

Additional context

• As of Nov 16
  Pioneer is currently passing 36 mandatory requirements, 1 optional requirements given in graphql-http spec
• Update as of Dec 25
  There are 79 audits in total, Pioneer achieved ✅ 45 pass and ⚠️ 34 warnings (optional)

[d-exclaimation]

I would try to best to match the optional requirements when possible or make any sense. I will also take note on how other implementation handle these requirements particularly apollo-server

[d-exclaimation]

Progress and more details on this will be here shown here.

Once I have Pioneer is a spot where it seemed pretty good and make sense, I would also try adding pioneer into the graphql-http list of spec-compliant implementations

[d-exclaimation]

Update (Late Dec 25th)

GraphQL over HTTP audit report

• 79 audits in total
• ✅ 76 pass
• ⚠️ 3 warnings (optional)

I feel as this is a pretty good state for now without making any massive changes

[d-exclaimation]

Related pull request

• audit Pioneer graphql/graphql-http#32