Update dependency rules_java to v9.6.1 #77

Job	Run time
Build scip-java CLI	5m 18s
maven-java25-demo	2m 35s
gradle-kotlin-flowext	3m 8s
maven-java17-spring-boot	2m 45s
maven-kotlin-json-kotlin-maven	2m 51s
gradle-kotlin-okio	4m 35s
bazel-java-examples	2m 37s
gradle-mixed-okio-jmh	4m 47s
gradle-java21-readiness	2m 49s
	31m 25s

Provide feedback