Updated version for container provisioning script to v0.11.0-alpha3.
Updated version for container provisioning script to v0.11.0-alpha3.

This commit updates the Mutagen version used in the container
provisioning script to v0.11.0-alpha3.

Signed-off-by: Jacob Howard <f862f167b85d41b225785c70d70808bc7337c1fe@havoc.io>

havoc-io/mutagen,havoc-io/mutagen