fix: precompute schemahash

[danstarns]

This PR exposes the schema hash when you use traceSchema so that you don't need to recompute it with each request.

const tracedScema = traceSchema({
  schema,
  adapter: // <-- See Adapters
});

const myServer = new GraphQLServerFooBar({
  schema,
  context: {
    GraphQLDebuggerContext: new GraphQLDebuggerContext({ schema: tracedSchema.schema, schemaHash: tracedSchema.schemaHash }),
  },
});

[danstarns]

Related:

• Slow query execution when using @graphql-debugger/trace-schema #287