chore(deps): update quay.io/skopeo/stable docker tag to v1.19.0

.drone.yml

@@ -16,7 +16,7 @@ steps:
 - name: markdown lint
   commands:
   - markdownlint *.md
-  image: git.cryptic.systems/volker.raschek/markdownlint:0.45.0
+  image: git.cryptic.systems/volker.raschek/markdownlint:0.44.0
   resources:
     limits:
       cpu: 150
@@ -399,7 +399,7 @@ steps:
       from_secret: container_image_registry_user
     DEST_CRED_PASSWORD:
       from_secret: container_image_registry_password
-  image: quay.io/skopeo/stable:v1.18.0
+  image: quay.io/skopeo/stable:v1.19.0
 
 - name: email-notification
   environment:
@@ -639,7 +639,7 @@ steps:
       from_secret: container_image_registry_user
     DEST_CRED_PASSWORD:
       from_secret: container_image_registry_password
-  image: quay.io/skopeo/stable:v1.18.0
+  image: quay.io/skopeo/stable:v1.19.0
 
 - name: email-notification
   environment: