Remove react-dom peer dep from react-apollo/hooks

[maclockard]

Fixes #3704

Looked through all the files for this package and I didn't see any usage of react-dom or usage of dom elements so its unnecessary as a peer dep and could cause confusion for folks using react without react-dom. I didn't check other packages, so its possible the peer dep is extraneous elsewhere as well.

Checklist:

• 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
• If this was a change that affects the external API used in GitHunt-React, update GitHunt-React and post a link to the PR in the discussion.

[apollo-cla]

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