refactor: make test happy which checks for specific error message

https://github.com/eclipse-thingweb/node-wot/blob/699e6b6cc640c60a1ca338050d496f59af7646f7/packages/binding-http/test/http-client-basic-test.ts#L115

Author: danielpeintner

packages/binding-http/src/http-client-impl.ts

@@ -433,6 +433,8 @@ export default class HttpClient implements ProtocolClient {
         if (HttpClient.isOAuthTokenExpired(result, this.credential)) {
             this.credential = await (this.credential as OAuthCredential).refreshToken();
             return await this._fetch(await this.credential.sign(request));
+        } else if (result.status === 401) {
+            throw new Error("Client error: Unauthorized");
         } else if (result.status >= 400) {
             // report generic error
             throw new Error(`request to ${request.url} failed, reason: HTTP status result ${result.status} `);