feat: add client side logging with slf4j #9568

Job	Run time
build(21) except self-service clients	6m 41s
build (11)	7m 10s
build(8) except for gapic-generator-java	4m 13s
build(8) for gapic-generator-java	3m 25s
build (17)	7m 27s
lint	31s
compatibility	1m 32s
dependency_analyzer_unit_test	13s
gapic-generator-java-bom	1m 58s
showcase (11)	7m 49s
showcase-clirr	3m 5s
showcase (17)	7m 42s
showcase-native	8m 37s
showcase (21)	7m 31s
unmanaged_dependency_check	6m 55s
	1h 14m 49s

Provide feedback