The new resin-multibuild and docker-progress versions widen the range
of errors caught by the 'balena push' and 'balena build' commands.
Change-type: patch
Signed-off-by: Paulo Castro <paulo@balena.io>
`version` used to be optional but it seems we recently had to make it a required parameter. However it really feels redundant when all it’s used for is to determine whether the command should issue a legacy user API key or a provisioning key.
This makes version optional but tries to figure it out by itself by reading os-release from the image's boot partition. This is not foul-proof however, and while it'll work with most recent images it won't work with all and in that case it'll bail out and only then warn the user to specify it via the --version argument.
Change-type: minor
