Rust

Fix formatting in Envoy metadata example. (#312) #2509

Job	Run time
bazel	1m 9s
msrv	2m 59s
licenses	14s
outdated	11s
nightly	30s
stable	37s
examples (http_headers)	32s
examples (envoy_filter_metadata)	22s
examples (grpc_auth_random)	13s
examples (http_body)	26s
examples (http_auth_random)	26s
reactors (http_body)	23s
examples (hello_world)	26s
reactors (hello_world)	23s
reactors (http_auth_random)	28s
examples (http_config)	21s
reactors (http_config)	22s
reactors (envoy_filter_metadata)	23s
audit	11s
reactors (http_headers)	23s
reactors (grpc_auth_random)	23s
	11m 22s

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