tools/docker: assorted updates for syz-env #14970

Job	Run time
dashboard	4m 6s
aux	4m 52s
arch (presubmit_arch_linux)	11m 2s
build	13m 13s
arch (presubmit_arch_freebsd)	6m 32s
gvisor	4m 9s
arch (presubmit_arch_netbsd)	4m 24s
old	6m 40s
arch (presubmit_arch_openbsd)	4m 23s
race	8m 41s
arch (presubmit_arch_darwin)	4m 21s
arch (presubmit_arch_windows)	3m 26s
race_dashboard	4m 25s
arch (presubmit_arch_executor)	3m 14s
	1h 23m 28s

Provide feedback