Switch Docker CI from gitlab to github

Adds buildx signing and helm chart publication.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

charts/smarter-device-manager/Chart.yaml

@@ -1,8 +1,8 @@
 apiVersion: v2
 name: smarter-device-manager
 description: smarter-device-manager chart for SMARTER edge devices
-home: https://getsmarter.io
-version: 0.0.7
+home: https://github.com/smarter-device-manager
+version: 0.0.5
 appVersion: v1.20.11
 kubeVersion: ">=1.16.0-0"
 keywords:
@@ -11,7 +11,7 @@ keywords:
   - hardware
 sources:
   - https://github.com/smarter-project/smarter-device-manager
-icon: https://gitlab.com/uploads/-/system/group/avatar/59012546/ARM1636_Project_Logo_ST2_RGB_V1.png
+
 annotations:
   artifacthub.io/changes: |
     - Fix template

charts/smarter-device-manager/values.yaml

@@ -4,7 +4,7 @@ application:
   appName: smarter-device-manager
 
 image:
-  repository: ghcr.io/smarter-project/smarter-device-manager
+  repository: registry.gitlab.com/smarter-project/smarter-device-manager
   # @default -- chart.appVersion
   tag: ""
   pullPolicy: IfNotPresent