fix deprecated old sbt build file syntax (#20949) #885

Job	Run time
Build Java Client JDK8 (samples/client/echo_api/java/apache-httpclient)	1m 12s
Build Java Client JDK8 (samples/client/echo_api/java/feign-gson)	58s
Build Java Client JDK8 (samples/client/echo_api/java/resttemplate)	1m 8s
Build Java Client JDK8 (samples/client/echo_api/java/okhttp-gson)	58s
Build Java Client JDK8 (samples/client/echo_api/java/resteasy)	50s
	5m 6s

Provide feedback