createStubRequest doesn't wrap errors in HTTPError

[chawes13]

https://github.com/LaunchPadLab/lp-requests/blob/master/src/http-error.js

This makes accessing the error different when working with lp-form. The appropriate information isn't passed to the errors object passed in as the first argument to onSubmitFail

export const addTodo = createStubRequest('ADD_TODO', ({ title }) => {
  if (title.toLowerCase().includes('nap')) throw new Error("There's no time for naps!")
  
  return { title, description: "", completed: false, id: 6 }
})

<AddTodoForm
    onSubmit={addTodo}
    onSubmitFail={(errors, _, submitError) => {
          // errors = {}, submitError = { errors: {}, meta: { error: 'No naps allowed' } }
          const message =
            errors.message || 'Could not add todo. Please try again'
    }}
/>

Alternatively, we could make try to make this request library independent and enhance the error message identification here: https://github.com/LaunchPadLab/lp-form/blob/master/src/middleware/wrapSubmissionPromise.js#L16