chore: untangling auth library parent and imported BOM #17549

Job	Run time
gitignore_correctness	1m 3s
root-pom	1m 39s
generate-readme	1m 7s
owlbot-yaml	1m 2s
owlbot-py	1m 6s
group_id_check_for_maps_libraries	2m 21s
gapic-bom	1m 48s
package_name_check	1m 2s
	11m 8s

Provide feedback