Ignore Mockito 5 (#7602)

.github/dependabot.yml

@@ -30,6 +30,9 @@ updates:
       - dependency-name: "net.sf.jt400:jt400"
         # using old version of this obscure artifact to test instrumentation of Java 1.1 bytecode
         versions: [ "(,)" ]
+      - dependency-name: "org.mockito:*"
+        # mockito 5 requires Java 11
+        versions: [ "[5,)]" ]
     rebase-strategy: "disabled"
     schedule:
       interval: "daily"