fix gc timeout

src/Database.js

@@ -79,7 +79,7 @@ export default function extendDatabase (Y /* :any */) {
 
       function garbageCollect () {
         return os.whenTransactionsFinished().then(function () {
-          if (os.gc1.length > 0 || os.gc2.length > 0) {
+          if (os.gcTimeout > 0 && (os.gc1.length > 0 || os.gc2.length > 0)) {
             if (!os.y.connector.isSynced) {
               console.warn('gc should be empty when not synced!')
             }
@@ -265,7 +265,7 @@ export default function extendDatabase (Y /* :any */) {
       }
     }
     * destroy () {
-      clearInterval(this.gcInterval)
+      clearTimeout(this.gcInterval)
       this.gcInterval = null
       this.stopRepairCheck()
     }