proper selection of account-level carrier with default routing (#63) (#64)

* update node image to the latest and most secure (#61)

Co-authored-by: Guilherme Rauen <g.rauen@cognigy.com>

* #62: dont modify refer-to host unless we have a dns name as outbound gateway

* added some tests and cleanup

* update drachtio-srf to latest

* gh action use node lts version

* revert and use node 18.x

.github/workflows/npm-ci.yml

@@ -11,7 +11,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v1
         with:
-          node-version: 14.x
+          node-version: 18.x
       - run: npm ci
       - run: npm run jslint
       - run: npm test