pkg/mgrconfig: export defaultValues function #18448

Job	Run time
race	6m 46s
dashboard	1m 52s
aux	4m 41s
race_dashboard	2m 52s
old	7m 0s
gvisor	4m 8s
build	5m 8s
arch (presubmit_arch_windows)	3m 21s
arch (presubmit_arch_linux)	10m 46s
arch (presubmit_arch_freebsd)	6m 13s
arch (presubmit_arch_netbsd)	3m 48s
arch (presubmit_arch_openbsd)	3m 42s
arch (presubmit_arch_executor)	3m 0s
arch (presubmit_arch_darwin)	3m 42s
	1h 6m 59s

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