Use client from props in Mutation component

[amneacsu]

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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[jbaxleyiii]

@amneacsu would you be able to add a test for this?

[amneacsu]

Hi @jbaxleyiii does this work? I have shamefully little experience with writing tests.

[hwillson]

Thanks for this PR @amneacsu! As soon as the tests go ✅ on the current run, we should be all set here.