[docs] Added Missing Hints in policy-reference #8767

Job	Run time
Generate Code	1m 34s
Go Lint	2m 44s
Rego PR checks	14s
Go Test (linux)	5m 1s
Go Test (darwin)	7m 41s
Check Generated	41s
Go compat build/test (ubuntu-22.04, 1.19)	2m 13s
Go compat build/test (macos-latest, 1.19)	2m 26s
Go Build (linux amd64)	4m 9s
Go Build (linux arm64)	2m 54s
Go Build (windows)	3m 54s
Go Build (darwin)	4m 15s
Go Race Detector	7m 41s
WASM	11s
docker image smoke test	43s
smoke-test-binaries (ubuntu-22.04, opa_linux_amd64)	18s
smoke-test-binaries (ubuntu-22.04, opa_linux_amd64_static, disabled)	23s
smoke-test-binaries (macos-latest, opa_darwin_amd64)	34s
smoke-test-binaries (windows-latest, opa_windows_amd64.exe)	44s
	48m 20s

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