Add client uptime metric #19264

Job	Run time
owlbot-yaml	1m 22s
gapic-bom	1m 59s
gitignore_correctness	1m 7s
package_name_check	1m 25s
group_id_check_for_maps_libraries	9m 8s
owlbot-py	1m 20s
root-pom	1m 38s
generate-readme	1m 16s
	19m 15s

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