Merge ~sylvain-pineau/plainbox-provider-docker:fix-registry into plainbox-provider-docker:master

[Sylvain Pineau]

Requires: https://code.launchpad.net/~sylvain-pineau/checkbox-core-snap/+git/checkbox-core-snap/+merge/386498

Fix the docker/deploy-registry job by calling htpasswd outside the container.

[Sylvain Pineau (sylvain-pineau)]

Let's land it, I wanna see if edge builds are fixed with this patch

diff --git a/units/docker.pxu b/units/docker.pxu
index e66001c..45acc16 100644
--- a/units/docker.pxu
+++ b/units/docker.pxu
@@ -318,13 +318,15 @@ template-unit: job
 id: docker/deploy-registry_{arch}
 user: root
 category_id: docker
-requires: snap.name == 'docker'
+requires:
+ snap.name == 'docker'
+ executable.name == 'htpasswd'
 command:
  set -e
  #A readable&writable path for docker snap
  auth_folder=/var/snap/docker/common/auth
  mkdir -p $auth_folder
- docker run --entrypoint htpasswd registry:2 -Bbn user passwd > $auth_folder/htpasswd
+ htpasswd -Bbn user passwd > $auth_folder/htpasswd
  docker run -d -p 5000:5000 --restart=always --name registry \
    -v $auth_folder:/auth \
    -e "REGISTRY_AUTH=htpasswd" \