Move GraphQL contact N+1 spec

What does this MR do and why?

@splattael pointed out:

Question With run_with_clean_state it's not longer a request API spec as it's not running post_graphql at all and is skipping controllers auth etc. Should we move it to, say, spec/graphql/types/issue_type_spec.rb? 🤔

We could still leave a simple happy-path request API spec if we want to. Nothing fancy.

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Related to #342914