update google cloud NIO provider (#1300)
update google cloud NIO provider (#1300)

* use a standard version of google cloud nio instead of a custom build
  org.broadinstitute:google-cloud-nio-GATK4-custom-patch:0.20.4-alpha-GCS-RETRY-FIX:shaded -> com.google.cloud:google-cloud-nio:0.81.0-alpha:shaded
alecw/picard,broadinstitute/picard,alecw/picard,broadinstitute/picard,alecw/picard,alecw/picard,broadinstitute/picard,broadinstitute/picard,broadinstitute/picard