transcribe and gather: silently discard listening events from ibm stt

lib/tasks/gather.js

@@ -484,6 +484,10 @@ class TaskGather extends Task {
     this.logger.debug({evt, bugname, finished}, 'Gather:_onTranscription');
     if (bugname && this.bugname !== bugname) return;
 
+    if (this.vendor === 'ibm') {
+      if (evt?.state === 'listening') return;
+    }
+
     evt = this.normalizeTranscription(evt, this.vendor, 1, this.language);
 
     /* count words for bargein feature */

lib/tasks/transcribe.js

@@ -226,6 +226,9 @@ class TaskTranscribe extends Task {
     const bugname = fsEvent.getHeader('media-bugname');
     if (bugname && this.bugname !== bugname) return;
 
+    if (this.vendor === 'ibm') {
+      if (evt?.state === 'listening') return;
+    }
     this.logger.debug({evt}, 'TaskTranscribe:_onTranscription - before normalization');
 
     evt = this.normalizeTranscription(evt, this.vendor, channel, this.language);