chore: also update dependencies on maintained stable branch

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

Author: susnux

.github/dependabot.yml

@@ -3,21 +3,38 @@
 
 version: 2
 updates:
+- package-ecosystem: github-actions
+  directory: "/"
+  schedule:
+    interval: weekly
+    timezone: Europe/Paris
+  open-pull-requests-limit: 10
+  labels:
+  - 3. to review
+  - dependencies
+
 - package-ecosystem: npm
   directory: "/"
   schedule:
     interval: weekly
     day: saturday
     time: "03:00"
     timezone: Europe/Paris
+  versioning-strategy: increase
   open-pull-requests-limit: 10
 
-- package-ecosystem: github-actions
+# maintained stable branch
+- package-ecosystem: npm
+  target-branch: stable5
   directory: "/"
   schedule:
     interval: weekly
+    day: saturday
+    time: "03:00"
     timezone: Europe/Paris
-  open-pull-requests-limit: 10
-  labels:
-  - 3. to review
-  - dependencies
+  versioning-strategy: increase
+  open-pull-requests-limit: 
+  ignore:
+    # no major updates on stable branches
+    - dependency-name: "*"
+      update-types: ["version-update:semver-major"]