Fixed a couple of doc issues

Use backticks instead of Javadoc code blocks in Asciidoc files.

Signed-off-by: Thomas Segismont <tsegismont@gmail.com>

Author: tsegismont

src/main/asciidoc/index.adoc

@@ -70,8 +70,7 @@ End-to-end headers are forwarded by the proxy, hop-by-hop headers are ignored.
 
 ==== Request authority
 
-As a transparent proxy, the request authority ({@code Host} header for HTTP/1.1, {@code :authority} pseudo header
-for HTTP/2) is preserved.
+As a transparent proxy, the request authority (`Host` header for HTTP/1.1, `:authority` pseudo header for HTTP/2) is preserved.
 
 You can override the request authority
 
@@ -80,8 +79,7 @@ You can override the request authority
 {@link examples.HttpProxyExamples#overrideAuthority}
 ----
 
-When the request authority is overridden, the {@code x-forwarded-host} header is set on the request to the origin server
-with the original authority value.
+When the request authority is overridden, the `x-forwarded-host` header is set on the request to the origin server with the original authority value.
 
 WARNING: changing the request authority can have undesirable side effects and can affect the proxied web server that might
 rely on the original request authority to handle cookies, URL redirects and such.