fix hangup headers (#583)

* fix hangup headers

* no need for callback

* fix test failure

---------

Co-authored-by: Dave Horton <daveh@beachdognet.com>

test/hangup-test.js

@@ -0,0 +1,53 @@
+const test = require('tape');
+const { sippUac } = require('./sipp')('test_fs');
+const clearModule = require('clear-module');
+const {provisionCallHook, provisionCustomHook} = require('./utils')
+const bent = require('bent');
+const getJSON = bent('json')
+
+process.on('unhandledRejection', (reason, p) => {
+  console.log('Unhandled Rejection at: Promise', p, 'reason:', reason);
+});
+
+function connect(connectable) {
+  return new Promise((resolve, reject) => {
+    connectable.on('connect', () => {
+      return resolve();
+    });
+  });
+}
+
+test('\'hangup\' custom headers', async(t) => {
+  clearModule.all();
+  const {srf, disconnect} = require('../app');
+
+  try {
+    await connect(srf);
+
+    // GIVEN
+    const verbs = [
+      {
+        verb: 'play',
+        url: 'https://example.com/example.mp3'
+      },
+      {
+        "verb": "hangup",
+        "headers": {
+          "X-Reason" : "maximum call duration exceeded"
+        }
+      }
+    ];
+
+    const from = 'hangup_custom_headers';
+    await provisionCallHook(from, verbs)
+
+    // THEN
+    await sippUac('uac-success-received-bye.xml', '172.38.0.10', from);
+    t.pass('play: succeeds when using single link');
+    disconnect();
+  } catch (err) {
+    console.log(`error received: ${err}`);
+    disconnect();
+    t.error(err);
+  }
+});