build: fix spell checker on macOS (#8744)
build: fix spell checker on macOS (#8744)

Use alternate invocation for setlocale that sucessfully sets a language
agnostic UTF-8 encoding as the locale.

Risk Level: low
Testing: n/a
Doc Changes: n/a
Release Notes: n/a
Fixes: #8742

Signed-off-by: Stephan Zuercher <12de3568c51b3e8be16eecacef359e62ce51b8cc@gmail.com>

envoyproxy/envoy,jrajahalme/envoy,istio/envoy,envoyproxy/envoy,lyft/envoy,lizan/envoy,lyft/envoy,jrajahalme/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,lyft/envoy,istio/envoy,eklitzke/envoy,lyft/envoy,eklitzke/envoy,eklitzke/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,eklitzke/envoy,envoyproxy/envoy,istio/envoy,lizan/envoy,lizan/envoy,lizan/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy-wasm,jrajahalme/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy-wasm,lyft/envoy,istio/envoy,envoyproxy/envoy-wasm,istio/envoy,jrajahalme/envoy,istio/envoy,jrajahalme/envoy,jrajahalme/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,istio/envoy,lizan/envoy,eklitzke/envoy,lizan/envoy,eklitzke/envoy,envoyproxy/envoy