tests: Add retry metrics tests to ITOtelGoldenMetrics #681

Job	Run time
filter	1m 1s
build(8) except for gapic-generator-java	3m 53s
build(21) except self-service clients	12m 44s
build(8) for showcase	8m 59s
dependency_analyzer_unit_test	1m 23s
build(25) except self-service clients	11m 39s
build (17)	13m 22s
showcase (21)	10m 36s
showcase (17)	10m 39s
build (11)	13m 20s
showcase (25)	10m 27s
gapic-generator-java-bom	2m 5s
showcase (11)	10m 54s
build(8) for gapic-generator-java	10m 41s
unmanaged_dependency_check	7m 11s
showcase-clirr	6m 6s
	2h 15m 0s

Provide feedback