Reduce the delete delay with an exponential wait #6962

Job	Run time
cross-i386	48s
test (ubuntu-20.04, 1.22.x, rootless, -race)	6m 46s
test (ubuntu-20.04, 1.22.x, rootless)	6m 26s
test (ubuntu-20.04, 1.22.x, -race)	7m 24s
test (ubuntu-20.04, 1.22.x)	6m 44s
test (ubuntu-20.04, 1.23.x, rootless, -race)	7m 9s
test (ubuntu-20.04, 1.23.x, rootless)	6m 28s
test (ubuntu-20.04, 1.23.x, -race)	7m 35s
test (ubuntu-20.04, 1.23.x)	6m 55s
test (ubuntu-20.04, 1.23.x, criu-dev)	7m 15s
test (ubuntu-24.04, 1.22.x, rootless, -race)	9m 13s
test (ubuntu-24.04, 1.22.x, rootless)	8m 59s
test (ubuntu-24.04, 1.22.x, -race)	8m 58s
test (ubuntu-24.04, 1.22.x)	5m 50s
test (ubuntu-24.04, 1.23.x, rootless, -race)	8m 57s
test (ubuntu-24.04, 1.23.x, rootless)	8m 58s
test (ubuntu-24.04, 1.23.x, -race)	8m 0s
test (ubuntu-24.04, 1.23.x)	7m 35s
test (ubuntu-24.04, 1.23.x, criu-dev)	7m 28s
test (actuated-arm64-6cpu-8gb, 1.23.x, rootless)	11m 0s
test (actuated-arm64-6cpu-8gb, 1.23.x)	7m 7s
all-done	1s
	2h 35m 36s

Provide feedback