fix header parsing

Author: gregfromstl

packages/service-utils/src/node/index.ts

@@ -76,13 +76,11 @@ function getHeader(
   headers: IncomingHttpHeaders | Headers,
   headerName: string,
 ): string | null {
-  const header = isNodeHeaders(headers)
-    ? headers[headerName]
+  return isNodeHeaders(headers)
+    ? Array.isArray(headers[headerName])
+      ? (headers[headerName]?.[0] ?? null)
+      : (headers[headerName] ?? null)
     : headers.get(headerName);
-  if (Array.isArray(header)) {
-    return header?.[0] ?? null;
-  }
-  return header ?? null;
 }
 
 export function extractAuthorizationData(