Add error handling to examples - Part 1

[laviniat1996]

This PR adds error handling to admin, auth and avm examples.

Because of no error handling, the user would get unhandled errors:

[UnhandledPromiseRejection: This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). The promise rejected with the reason "#<Object>".] {
  code: 'ERR_UNHANDLED_REJECTION'
}

With the addition of error handling, the user gets a much specific error, thus knowing that the script did run, but there's a problem within the script setup:

Error. Please check if all the parameters are configured correctly.