chore: add docker secret to env

.agola/config.yml

@@ -19,6 +19,9 @@ runs:
         runtime:
           containers:
             - image: gcr.io/kaniko-project/executor:debug
+        environment:
+          DOCKERAUTH:
+            from_variable: dockerauth            
         shell: /busybox/sh
         steps:
           - restore_workspace:
@@ -33,6 +36,6 @@ runs:
                   }
                 }
                 EOF
-          - run: /kaniko/executor --destination code.icb4dc0.de/prskr/blog:latest
+          - run: /kaniko/executor --destination code.icb4dc0.de/prskr/blog:$AGOLA_GIT_COMMITSHA --context dir:///root/project/ --dockerfile /root/project/Dockerfile
         depends:
           - checkout code