Improve context types

[Hugodby]

• Allow declaration merging for DefaultContext
• Use DefaultContext instead of any
• Tests: Linked the package manually
• Issues: Proper types for link context #9249 Support generic context type on ContextSetter and setContext #8902

[apollo-cla]

@Hugodby: Thank you for submitting a pull request! Before we can merge it, you'll need to sign the Apollo Contributor License Agreement here: https://contribute.apollographql.com/

[changeset-bot]

🦋 Changeset detected

Latest commit: 75a928d

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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[jerelmiller]

Hey @Hugodby 👋 ! Thanks so much for this contribution! Would you be willing to add a changeset to this PR? You can do so by running npx changeset and following the prompts. This will ensure this PR adds the proper version bump and adds an entry to our changelog.

[Hugodby]

Hello @jerelmiller , thank you for your message. I just added the changeset.

[jerelmiller]

Hey @Hugodby thanks for your patience! We had some intermittent test failures on main that we wanted to shore up before we could get to other PRs.

We will get this PR tended to soon!

[alessbell]

LGTM, thanks @Hugodby!