fixing lint error etc

Author: leftieFriele

examples/failing.js

@@ -10,6 +10,7 @@ try {
         path: '/',
         method: 'GET',
     });
+    // eslint-disable-next-line no-unused-vars
 } catch (_) {
     // Mute the first one, next request should hit an open breaker
 }

lib/http-client.js

@@ -79,7 +79,11 @@ export default class HttpClient {
 
         if (fallback) {
             this.#hasFallback = true;
-            this.#fallback(fallback);
+            if (typeof fallback === 'string') {
+                this.#fallback(() => fallback);
+            } else {
+                this.#fallback(fallback);
+            }
         }
     }
 
@@ -164,6 +168,7 @@ export default class HttpClient {
 export class HttpClientError extends Error {
     // Not sure if there is a need for this tbh, but I threw it in there so we can see how it feels.
     static ServerDown = 'EOPENBREAKER';
+
     constructor(message, { code, cause, options }) {
         super(message);
         this.name = 'HttpClientError';