BUG: Generic type 'ExecutionResult<TData>' requires between 0 and 1 type arguments
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### Summary

TypeError following https://github.com/graphile/postgraphile/commit/73fe8011d902f14c7ba29771e162bde81d6ce5b0

`Generic type 'ExecutionResult<TData>' requires between 0 and 1 type arguments`

It seems the author is assuming a type definition of `ExecutionResult` that's incompatible with graphql 14.*, but this is an accepted version of graphql in postgraphile's package.json dependencies 

### Steps to reproduce

Run postraphile 12.1.0 alongside graphql 14.7.0

### Expected results

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### Actual results

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### Additional context

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### Possible Solution

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