Exclude JUnit 6 from Dependabot (requires Java 17)

Author: ljacqu

.github/dependabot.yml

@@ -6,6 +6,9 @@ updates:
     interval: daily
   open-pull-requests-limit: 10
   target-branch: dependencies
+  ignore:
+    - dependency-name: "org.junit.jupiter:junit-jupiter-api"
+      versions: ">= 6"
 - package-ecosystem: "github-actions"
   directory: "/"
   schedule: