docs: Add arrays to composite values section #10186

Job	Run time
Rego PR checks	1m 39s
Go Lint	1m 42s
Generate Code	1m 9s
YAML Lint	17s
Go Build (linux amd64)	2m 32s
Go Build (linux arm64)	2m 3s
Check Generated	25s
Go Race Detector	6m 10s
Go Test (linux)	4m 29s
Go Build (linux arm64GO_TAGS="-tags=opa_no_oci")	2m 6s
Go Test (darwin)	3m 49s
Go Build (windows amd64)	2m 22s
WASM	10s
Go compat build/test (ubuntu-22.04, 1.20)	4m 1s
Go Build (darwin amd64)	1m 29s
Go Build (darwin arm64)	43s
Go compat build/test (macos-14, 1.20)	3m 56s
docker image smoke test	31s
smoke-test-binaries (linux, ubuntu-22.04, opa_linux_amd64, amd64)	16s
smoke-test-binaries (linux, ubuntu-22.04, opa_linux_amd64_static, amd64, disabled)	10s
smoke-test-binaries (darwin, macos-13, opa_darwin_amd64, amd64)	36s
smoke-test-binaries (darwin, macos-14, opa_darwin_arm64_static, arm64, disabled)	15s
smoke-test-binaries (windows, windows-latest, opa_windows_amd64.exe, amd64)	39s
	41m 29s

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