fix(audits): inconsistency between D6D5 and 6A70

[DoctorJohn]

D6D5 and 6A70 essentially perform the same audit check. However, while 6A70 checks that the execution result has no errors, D6D5 does not. This PR updates D6D5 to also check that the execution result has no errors (i.e, make both audit functions do the same assertions).

Relevant code:

graphql-http/src/audits/server.ts

Lines 460 to 498 in a49c45b

	audit(
	'D6D5',
	'MAY allow URL-encoded JSON string {variables} parameter in GETs when accepting application/graphql-response+json',
	async () => {
	const url = new URL(await getUrl(opts.url));
	url.searchParams.set(
	'query',
	'query Type($name: String!) { __type(name: $name) { name } }',
	);
	url.searchParams.set('variables', JSON.stringify({ name: 'sometype' }));
	const res = await fetchFn(url.toString(), {
	method: 'GET',
	headers: {
	accept: 'application/graphql-response+json',
	},
	});
	ressert(res).status.toBe(200);
	},
	),
	audit(
	'6A70',
	'MAY allow URL-encoded JSON string {variables} parameter in GETs when accepting application/json',
	async () => {
	const url = new URL(await getUrl(opts.url));
	url.searchParams.set(
	'query',
	'query Type($name: String!) { __type(name: $name) { name } }',
	);
	url.searchParams.set('variables', JSON.stringify({ name: 'sometype' }));
	const res = await fetchFn(url.toString(), {
	method: 'GET',
	headers: {
	accept: 'application/json',
	},
	});
	ressert(res).status.toBe(200);
	await ressert(res).bodyAsExecutionResult.notToHaveProperty('errors');
	},
	),

The check that's only present in 6A70 but not in D6D5:

graphql-http/src/audits/server.ts

Line 496 in a49c45b

await ressert(res).bodyAsExecutionResult.notToHaveProperty('errors');

[enisdenjo]

There is a fine detail here: application/json uses 200 almost always (true legacy servers truly always) and the only way to detect an error there is by looking at the errors entry - which is what the test checks; on the other hand, application/graphql-response+json will return a 400 in case of invalid parameters, not needing to check the errors entry.

But nevertheless, the extra assertion wont hurt!