Handle use of containerd driver type with elastic-agent images

[jsoriano]

Docker for Windows and Mac include a beta feature that enables the containerd storage for images. When this plugin is enabled, elastic-agent doesn't start, with an error like the following one:

/usr/local/bin/docker-entrypoint: line 14: exec: elastic-agent: not found

When this feature is enabled, it is available in docker info:

 Storage Driver: stargz
  driver-type: io.containerd.snapshotter.v1

Try to handle this in elastic-package. I see some options:

• Use docker-compose to "fix" the permission issues if possible.
• Detect if this driver type is used, and if elastic-package stack up fails, tell the user to disable this feature.

Issue mentioned also in elastic/elastic-agent#82 (comment).

[bplies-ATX]

A new reference in elastic/elastic-agent#82 (comment)