Doc: add new policy to cognito sample Readme #1073

Job	Run time
Android Device Farm	2m 23s
check-codegen-edits	4s
consistent-crt-version	4s
check-docs	38s
java-compat (8)	6h 0m 13s
java-compat (11)	6m 49s
java-compat (17)	6m 58s
linux-compat (manylinux2014-x64)	2m 8s
linux-compat (al2-x64)	51s
linux-compat (fedora-34-x64)	1m 43s
linux-compat (rhel8-x64)	1m 12s
linux-musl-armv7	32m 22s
linux-musl (alpine-3.16-x64)	49s
linux-musl (alpine-3.16-arm64)	3m 25s
linux-musl (openwrt-x64-openjdk8)	44s
linux-smoke-tests (17)	2m 8s
osx (8)	8m 57s
osx (11)	8m 0s
osx (17)	6m 51s
raspberry (raspbian-bullseye)	6m 9s
windows (8)	9m 12s
windows (11)	8m 13s
windows (17)	7m 40s
	7h 57m 33s

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