lxd: path cannot have extra forward slashes

[kalikiana]

After double-checking that the logic for mounting the project folder on the Snapcraft side I ended up finding that LXD can end up claiming the device exists without actually mounting it. In that case lxc device remove aborts with internal errors.
Apparently the LXD issue can be avoided by getting rid of a leading / in the mounted path.

This fixes Could not find snap/snapcraft.yaml.

Notes:

• I'm not especially happy with the test side of this, it's a virtually invisible change. Suggestions would be welcome.
• Maybe we should be moving to using lxc edit for configuration as it can be used to fix containers that would be stuck using dedicated commands.

[sergiusens]

Once @ElOpio's branch lands for container testing we can extend these tests, just add a personal note or bug in launchpad to keep track of it.

[come-maiz]

@kalikiana I see that path still has two slashes:

'path=//root/build_basic'

Could that be a problem?

I was able to build the snap in containers many times, so +1, just pending on the answer to that question.

[kalikiana]

@ElOpio If by still you mean an existing container, yes, the bug won't be fixed for that container. As mentioned in the description, lxc config edit seems to be the only way to fix that. I'm looking into that, but it'll be more invasive changes.