Updating cert-manager instructions #1709

Job	Run time
lint (1.21.x, ubuntu-latest)	4m 18s
govet (1.21.x, ubuntu-latest)	3m 9s
Shellcheck (1.21.x)	23s
Check for vulnerable dependencies (1.21.x)	59s
gotest (1.21.x, ubuntu-latest)	3m 15s
operator (1.21.x, ubuntu-latest)	5m 30s
test-policy-binding (1.21.x, ubuntu-latest)	8m 18s
test-kes (1.21.x, ubuntu-latest)	4m 44s
helm-floor (1.21.x, ubuntu-latest)	3m 25s
helm (1.21.x, ubuntu-latest)	2m 57s
test-tenant (1.21.x, ubuntu-latest)	3m 32s
test-tenant-upgrade (1.21.x, ubuntu-latest)	4m 53s
	45m 23s

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