Switch header for incoming protocol (#9837)

* Switch header for incoming protocol

* Update policy-doc-surrogate-key

Author: rachelwhitton

src/middleware.ts

@@ -228,8 +228,8 @@ export function middleware(request: NextRequest) {
   // See https://github.com/pantheon-systems/documentation/issues/9791
   // for more context.
   const siteMachineName = process.env.PANTHEON_SITE_MACHINE_NAME || "documentation-in-nextjs";
-  const incomingProtocol = request.headers.get('x-proto') || '';
-  const policyDocSurrogateKey = request.headers.get('policy-doc-surrogate-key') || '';
+  const incomingProtocol = request.headers.get('x-forwarded-proto') || '';
+  const policyDocSurrogateKey = request.headers.get('Policy-Doc-Surrogate-Key') || '';
   if (incomingProtocol === 'http' && policyDocSurrogateKey) {
       url.protocol = "https:";
       url.hostname = policyDocSurrogateKey;