fix: variables incorrectly removed in BatchHttpLink

[alessbell]

Fixes a bug in #10754 which caused all variables to be removed from BatchHttpLink requests. Added the same integration test used in HttpLink's test suite.

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: a7f3007

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	36.55 KB (+0.02% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/main.cjs"	42.95 KB (-0.01% 🔽)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/index.js"	32.43 KB (-0.01% 🔽)
import { ApolloProvider } from "dist/react/index.js"	1.3 KB (0%)
import { useQuery } from "dist/react/index.js"	4.34 KB (0%)
import { useLazyQuery } from "dist/react/index.js"	4.66 KB (0%)
import { useMutation } from "dist/react/index.js"	2.57 KB (0%)
import { useSubscription } from "dist/react/index.js"	2.34 KB (0%)
import { useSuspenseQuery } from "dist/react/index.js"	3.45 KB (0%)
import { useBackgroundQuery } from "dist/react/index.js"	2.89 KB (0%)
import { useReadQuery } from "dist/react/index.js"	1.65 KB (0%)
import { useFragment } from "dist/react/index.js"	2.12 KB (0%)

[jerelmiller]

Thanks for fixing this!

[jerelmiller]

Does this test need to call resolve anywhere to get it to complete correctly?

[jerelmiller]

I guess the tests pass, so that answers my question 😄

[alessbell]

It's called in makeCallback, but yeah a bit hard to see :D