chore: gcr.io auth has container registry scope (#3)
chore: gcr.io auth has container registry scope (#3)

The `gcr.io` auth helper needs to have scopes specified that
authenticates for reading and/or writing to the Google Container
Registry.  If the scopes are not specified, the auth helper will
fail to authenticate.

Now, if the options specified to the `gcr.io` helper do not
include scopes, one of the scopes

* https://www.googleapis.com/auth/devstorage.read_write
* https://www.googleapis.com/auth/devstorage.read_only

are automatically used depending on whether read or read and
write capabilities are needed.
google/nodejs-container-image-builder,google/nodejs-container-image-builder