Preserve MQTT TLS connection time and internal DMA headroom

.github/workflows/run-unit-tests.yml

@@ -192,6 +192,10 @@ jobs:
         run: |
           python3 -B test/test_mqtt_transport_results.py -v
           python3 -B test/test_mqtt_tls_security.py -v
+          python3 -B test/test_mqtt_network_timeout.py -v
+          python3 -B test/test_mqtt_connection_admission.py -v
+          python3 -B test/test_mqtt_handshake_scheduler.py -v
+          python3 -B test/test_mqtt_diagnostics.py -v
 
       - name: Verify DNS lease restoration and bounded diagnostics
         run: python3 -B test/test_network_dns.py -v