fix(vector sink): cert verification with proxy enabled (vectordotdev#17651)

fixes vectordotdev#17629

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---------

Co-authored-by: neuronull <[email protected]>

Author: joemiller

src/sinks/vector/config.rs

@@ -16,6 +16,7 @@ use crate::{
         AcknowledgementsConfig, GenerateConfig, Input, ProxyConfig, SinkConfig, SinkContext,
         SinkHealthcheckOptions,
     },
+    http::build_proxy_connector,
     proto::vector as proto,
     sinks::{
         util::{
@@ -24,7 +25,7 @@ use crate::{
         },
         Healthcheck, VectorSink as VectorSinkType,
     },
-    tls::{tls_connector_builder, MaybeTlsSettings, TlsEnableableConfig},
+    tls::{MaybeTlsSettings, TlsEnableableConfig},
 };
 
 /// Configuration for the `vector` sink.
@@ -209,23 +210,7 @@ fn new_client(
     tls_settings: &MaybeTlsSettings,
     proxy_config: &ProxyConfig,
 ) -> crate::Result<hyper::Client<ProxyConnector<HttpsConnector<HttpConnector>>, BoxBody>> {
-    let mut http = HttpConnector::new();
-    http.enforce_http(false);
-
-    let tls = tls_connector_builder(tls_settings)?;
-    let mut https = HttpsConnector::with_connector(http, tls)?;
-
-    let settings = tls_settings.tls().cloned();
-    https.set_callback(move |c, _uri| {
-        if let Some(settings) = &settings {
-            settings.apply_connect_configuration(c);
-        }
-
-        Ok(())
-    });
-
-    let mut proxy = ProxyConnector::new(https).unwrap();
-    proxy_config.configure(&mut proxy)?;
+    let proxy = build_proxy_connector(tls_settings.clone(), proxy_config)?;
 
     Ok(hyper::Client::builder().http2_only(true).build(proxy))
 }