Fix: book-trips.tsx error

[Barrosg99]

Missing '!' causes "Variable $launchIds of type [ID]! used in position expecting type [ID!]." error on book-trips.tsx

[apollo-cla]

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[StephenBarlow]

Hi @Barrosg99, I believe you might have put a ! in the incorrect spot in your bookTrips schema definition? This is the definition as written in the "Build a schema" chapter:

type Mutation {
  bookTrips(launchIds: [ID]!): TripUpdateResponse!
  cancelTrip(launchId: ID!): TripUpdateResponse!
  login(email: String): User
}

In terms of what the tutorial is expecting by default, I believe this is correct as-is 🤔