[docs] Correct envoy tutorial mistake #8716

Job	Run time
Go Lint	2m 16s
Generate Code	1m 51s
Rego PR checks	14s
WASM	13s
Go Build (linux amd64)	3m 30s
Go Build (linux arm64)	2m 48s
Go Build (windows)	4m 0s
Go Build (darwin)	1m 50s
Check Generated	30s
Go Test (linux)	5m 33s
Go Test (darwin)	7m 13s
Go compat build/test (ubuntu-22.04, 1.19)	5m 6s
Go compat build/test (macos-latest, 1.19)	8m 15s
Go Race Detector	7m 30s
docker image smoke test	35s
smoke-test-binaries (ubuntu-22.04, opa_linux_amd64)	19s
smoke-test-binaries (ubuntu-22.04, opa_linux_amd64_static, disabled)	16s
smoke-test-binaries (macos-latest, opa_darwin_amd64)	1m 46s
smoke-test-binaries (windows-latest, opa_windows_amd64.exe)	43s
	54m 28s

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