exec gather after finishing queue

lib/tasks/cognigy/index.js

@@ -241,15 +241,15 @@ class Cognigy extends Task {
 
   async _onBotFinalPing(cs, ep) {
     this.logger.info({prompts: this.prompts}, 'Cognigy:_onBotFinalPing');
-    this._enqueueTask(async() => {
+    try {
+      // lets wait until we have finished processing the speech before 
+      // starting a gather...
+      await this.taskQueue.lastPromise;
       const gatherTask = this._makeGatherTask();
       await gatherTask.exec(cs, ep, this);
-      try {
-        await sayTask.exec(cs, ep, this);
-      } catch (err) {
-        this.logger.info({err}, 'Cognigy gather task returned error');
-      }
-    });
+    } catch (err) {
+      this.logger.info({err}, 'Cognigy gather task returned error');
+    }
   }
 
   async _onBotUtterance(cs, ep, evt) {