Standardize security guards documentation for upstream contribution #9

Job	Run time
test (ubuntu-latest)	6h 5m 0s
build (macos-latest, aarch64-apple-darwin, default)	10m 21s
build (windows-latest, x86_64-pc-windows-msvc, default)	18m 46s
lint	3m 48s
test (windows-latest)	6h 0m 5s
build (ubuntu-22.04-arm, aarch64-unknown-linux-musl, default)	6m 34s
build (ubuntu-latest, x86_64-unknown-linux-musl, jemalloc)	5m 15s
	12h 49m 49s

Provide feedback