chore: Change dependabot strategy to increase for composer

Signed-off-by: Julius Knorr <jus@bitgrid.net>

Author: juliusknorr

.github/dependabot.yml

@@ -24,6 +24,7 @@ updates:
     day: saturday
     time: "03:00"
     timezone: Europe/Paris
+  versioning-strategy: "increase"
   open-pull-requests-limit: 10
   labels:
     - "3. to review"