processRequest does not support multiple accept types

[Jomik]

The currently bundle GraphiQL sends multiple accept types when sending a request:
Slightly related to #203

See

graphql-helix/packages/core/lib/process-request.ts

Line 90 in 8970773

const isEventStream = accept === "text/event-stream";

I currently get accept = 'application/json, multipart/mixed, text/event-stream'
Maybe this should be updated to use includes.
Also, is there a reason to not check for multipart/mixed?

[Jomik]

Fixed by #160 I assume

[n1ru4l]

This is now fixed within https://github.com/contra/graphql-helix/releases/tag/graphql-helix%401.11.0