chore: update dependency graphql to ^15.9.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
graphql	^15.8.0 -> ^15.9.0

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Release Notes

graphql/graphql-js (graphql)

### [`v15.9.0`](https://togithub.com/graphql/graphql-js/compare/v15.8.0...511e0f1f1a0f3cbef04f731cf2dd534fb946e0a5) [Compare Source](https://togithub.com/graphql/graphql-js/compare/v15.8.0...v15.9.0)

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Configuration

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🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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This PR has been generated by Mend Renovate. View repository job log here.

[coveralls]

Pull Request Test Coverage Report for Build 9621080850

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 54.772%

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Totals
Change from base Build 9621050209:	0.0%
Covered Lines:	9566
Relevant Lines:	12465

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💛 - Coveralls