function validateOptsBinariesAsync (opts) {
  return new Promise(function (resolve, reject) {
    if (opts.binaries) {
      if (!Array.isArray(opts.binaries)) {
        reject(new Error('Additional binaries should be an Array.'))
        return
      }
      // TODO: Presence check for binary files, reject if any does not exist
    }
    resolve()
  })
}
This function returns a promise validating opts.binaries, the additional binaries to be signed along with the discovered enclosed components.
@function
@param {Object} opts - Options.
@returns {Promise} Promise.