test: remove duplicate enum def

[dpilch]

Description of changes

It is not possible to use a.ref in a custom query/mutation currently. Previously the enum would need to be defined twice (once as the top-level enum type and then in the custom query/mutation).

EchoQueryStatus: a.enum([
  'PROGRESS',
  'COMPLETED',
]),
// Custom query
echoQuery: a
  .query()
  .arguments({
    status: a.enum(['PROGRESS', 'COMPLETED']),
  })

A change to the data schema builder now auto-creates the top-level enum type. This resulted in duplicate enum definition for EchoQueryStatus in our tests.

enum EchoQueryStatus {
  PROGRESS
  COMPLETED
}

# defined twice
enum EchoQueryStatus {
  PROGRESS
  COMPLETED
}

Description of how you validated changes

E2E tests

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