website/docs: Fix nginx proxy_pass directive documentation #21632

Job	Run time
lint-golint	1m 0s
test-unittest	2m 46s
ci-outpost-mark	1s
build-container (proxy)	2m 43s
build-binary (proxy, linux, amd64)	1m 37s
build-container (ldap)	2m 3s
build-binary (proxy, linux, arm64)	1m 50s
build-container (radius)	2m 0s
build-binary (ldap, linux, amd64)	1m 36s
build-container (rac)	2m 13s
build-binary (ldap, linux, arm64)	1m 50s
build-binary (radius, linux, amd64)	1m 34s
build-binary (radius, linux, arm64)	1m 48s
build-binary (rac, linux, amd64)	1m 26s
build-binary (rac, linux, arm64)	1m 35s
	26m 2s

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