fix slice problem

lib/githubFetcher.js

@@ -37,6 +37,7 @@ class GitHubFetcher {
     const etagPromise = checkEtag ? this.store.etag(request.type, request.url) : Q(null);
     return etagPromise.then(etag => {
       let options = self._addTokenOption(request, { headers: {} });
+      const token = options.headers.authorization.slice(6);
       if (typeof options === 'number') {
         // if we get back a number, all tokens have been benched so we have to requeue and wait.
         return self._requeueBenched(request, options);
@@ -59,7 +60,6 @@ class GitHubFetcher {
           // we have already retried. Retries will be done with full permission tokens so if there is still
           // a problem then we are done here.
           if ([401, 403, 404].includes(response.statusCode)) {
-            const token = options.headers.authorization.slice(6);
             request.addMeta({ token: `${token.slice(0, 2)}..${token.slice(-2)}` });
             if (request.attemptCount && request.attemptCount > 1) {
               return request.markDead('Bailed', `After ${request.attemptCount} tries.`);