required arguments with default values shouldn't be required in operation variables

[awinograd]

Describe the bug

input ContactPointInput {
  rank: Int! = 1
  value: String!
}

type Mutation {
    addContactPoint(contactPoint: [ContactPointInput!]!): Boolean!
}

        await client.request(
          graphql(
            `
              mutation TestMutation($contactPoint: [ContactPointInput!]!) {
                addContactPoint(contactPoint: $contactPoint)
              }
            `,
          ),
          {
            contactPoint: [
              {
                value: '5551235555',
              },
            ],
          },
        );

Reproduction

No response

gql.tada version

1.2.1

Validations

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