Parse incoming JSON asynchronously if possible

[phryneas]

Since we have support for multipart responses, we had to switch away from Response.json because we had to parse the response manually.
At least since it has been added to this repository, HttpLink always used Response.text() followed by JSON.parse. Unfortunately, that moved parsing to the main thread, and it became blocking, which can be problematic with very large responses.

This PR tries to move parsing off the main thread where possible. Queries that will have a multipart response are excluded from this - I had managed to make them async by creating a new Request object, followed by calling .json on that, but that would (after a short moment) still block the main thread and just make things slower.

The tests have been updated to have Response present in our test environment, so currently all of our tests are running this new behaviour.

We have to make a call with this PR: 89f99f9 adds quite a bit complexity. It's necessary to have the response body available in case of a ParsingError. We could decide to keep response off the error object in those cases, and work with the more simple logic I had in place before.

Checklist:

• If this PR contains changes to the library itself (not necessary for e.g. docs updates), please include a changeset (see CONTRIBUTING.md)
• If this PR is a new feature, please reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests

[changeset-bot]

🦋 Changeset detected

Latest commit: 0155c66

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@apollo/client	Patch

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[github-actions]

size-limit report 📦

Path	Size
dist/apollo-client.min.cjs	37.35 KB (+0.2% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/main.cjs"	43.89 KB (+0.33% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/main.cjs" (production)	42.46 KB (+0.34% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/index.js"	32.66 KB (+0.43% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/index.js" (production)	31.43 KB (+0.51% 🔺)
import { ApolloProvider } from "dist/react/index.js"	1.21 KB (0%)
import { ApolloProvider } from "dist/react/index.js" (production)	1.2 KB (0%)
import { useQuery } from "dist/react/index.js"	4.27 KB (0%)
import { useQuery } from "dist/react/index.js" (production)	4.08 KB (0%)
import { useLazyQuery } from "dist/react/index.js"	4.58 KB (0%)
import { useLazyQuery } from "dist/react/index.js" (production)	4.4 KB (0%)
import { useMutation } from "dist/react/index.js"	2.52 KB (0%)
import { useMutation } from "dist/react/index.js" (production)	2.51 KB (0%)
import { useSubscription } from "dist/react/index.js"	2.24 KB (0%)
import { useSubscription } from "dist/react/index.js" (production)	2.2 KB (0%)
import { useSuspenseQuery } from "dist/react/index.js"	4.76 KB (0%)
import { useSuspenseQuery } from "dist/react/index.js" (production)	4.19 KB (0%)
import { useBackgroundQuery } from "dist/react/index.js"	4.28 KB (0%)
import { useBackgroundQuery } from "dist/react/index.js" (production)	3.7 KB (0%)
import { useReadQuery } from "dist/react/index.js"	2.96 KB (0%)
import { useReadQuery } from "dist/react/index.js" (production)	2.91 KB (0%)
import { useFragment } from "dist/react/index.js"	2.08 KB (0%)
import { useFragment } from "dist/react/index.js" (production)	2.03 KB (0%)

[phryneas]

This has already been handled in the parseJsonBody method so we can remove it here.

[phryneas]

After further testing, it seems that no browser actually moves the parsing off-thread (although the spec would allow for it) and it will be blocking either way, so I will close this.
I'll open a new PR with some code deduplication I noticed during this PR.

[phryneas]

Extracted that to #11470 - closing this.