Omit api key if none is provided

Author: stanleyphu

src/HttpClient.ts

@@ -92,14 +92,15 @@ export default class ApiClient implements HttpClient {
         const fetchRequestOptions: FetchRequestOptions = {
             method,
             headers: {
-                Authorization: `ApiKey ${this.config.apiKey}`,
                 'User-Agent': `warrant-node/${version}`,
                 'Content-Type': "application/json"
             },
         };
 
         if (requestOptions?.apiKey) {
             fetchRequestOptions.headers['Authorization'] = `ApiKey ${requestOptions.apiKey}`;
+        } else if (this.config.apiKey) {
+            fetchRequestOptions.headers['Authorization'] = `ApiKey ${this.config.apiKey}`;
         }
 
         if (requestOptions?.baseUrl) {