Problem with Lab18 uaa-guard-proxy: ERR None of the buildpacks detected a compatible application

cf logs uaa-guard-proxy --recent

Retrieving logs for app uaa-guard-proxy in org xxxxx_test / space test as xxxxxxxxxxxxxxxxxxxxxx...

2018-09-15T18:08:04.12+0530 [API/10] OUT Created app with guid c17aa997-3363-4c5d-b066-368a7263479e
2018-09-15T18:08:05.80+0530 [API/2] OUT Uploading bits for app with guid c17aa997-3363-4c5d-b066-368a7263479e
2018-09-15T18:15:45.71+0530 [API/19] OUT Updated app with guid c17aa997-3363-4c5d-b066-368a7263479e ({"environment_json"=>"[PRIVATE DATA HIDDEN]"})
2018-09-15T18:16:52.81+0530 [API/16] OUT Updated app with guid c17aa997-3363-4c5d-b066-368a7263479e ({"environment_json"=>"[PRIVATE DATA HIDDEN]"})
2018-09-15T18:19:06.33+0530 [API/8] OUT Creating build for app with guid c17aa997-3363-4c5d-b066-368a7263479e
2018-09-15T18:19:07.52+0530 [API/8] OUT Updated app with guid c17aa997-3363-4c5d-b066-368a7263479e ({"state"=>"STARTED"})
2018-09-15T18:19:07.70+0530 [STG/0] OUT Downloading binary_buildpack...
2018-09-15T18:19:07.70+0530 [STG/0] OUT Downloading nodejs_buildpack...
2018-09-15T18:19:07.70+0530 [STG/0] OUT Downloading java_buildpack...
2018-09-15T18:19:07.70+0530 [STG/0] OUT Downloading ruby_buildpack...
2018-09-15T18:19:07.70+0530 [STG/0] OUT Downloading php_buildpack...
2018-09-15T18:19:07.74+0530 [STG/0] OUT Downloaded java_buildpack
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloaded php_buildpack
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloading dotnet_core_buildpack...
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloaded ruby_buildpack
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloading staticfile_buildpack...
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloading go_buildpack...
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloaded nodejs_buildpack
2018-09-15T18:19:07.76+0530 [STG/0] OUT Downloading dotnet_core_buildpack_beta...
2018-09-15T18:19:07.81+0530 [STG/0] OUT Downloaded staticfile_buildpack
2018-09-15T18:19:07.81+0530 [STG/0] OUT Downloading hwc_buildpack...
2018-09-15T18:19:07.82+0530 [STG/0] OUT Downloaded dotnet_core_buildpack_beta
2018-09-15T18:19:07.82+0530 [STG/0] OUT Downloading python_buildpack...
2018-09-15T18:19:07.83+0530 [STG/0] OUT Downloaded hwc_buildpack
2018-09-15T18:19:07.86+0530 [STG/0] OUT Downloaded python_buildpack
2018-09-15T18:19:07.86+0530 [STG/0] OUT Downloaded binary_buildpack
2018-09-15T18:19:07.93+0530 [STG/0] OUT Downloaded go_buildpack
2018-09-15T18:19:08.87+0530 [STG/0] OUT Downloaded dotnet_core_buildpack
2018-09-15T18:19:08.87+0530 [STG/0] OUT Cell 850bb788-0cb8-4092-b839-32661cb636dc creating container for instance e3ba9750-03fc-4390-a910-e3b17ca3c163
2018-09-15T18:19:09.35+0530 [STG/0] OUT Cell 850bb788-0cb8-4092-b839-32661cb636dc successfully created container for instance e3ba9750-03fc-4390-a910-e3b17ca3c163
2018-09-15T18:19:09.85+0530 [STG/0] OUT Downloading app package...
2018-09-15T18:19:09.91+0530 [STG/0] OUT Downloaded app package (9K)
** 2018-09-15T18:19:11.56+0530 [STG/0] ERR None of the buildpacks detected a compatible application**
2018-09-15T18:19:11.59+0530 [STG/0] OUT Exit status 222
2018-09-15T18:19:12.00+0530 [STG/0] OUT Cell 850bb788-0cb8-4092-b839-32661cb636dc stopping instance e3ba9750-03fc-4390-a910-e3b17ca3c163
2018-09-15T18:19:12.00+0530 [STG/0] OUT Cell 850bb788-0cb8-4092-b839-32661cb636dc destroying container for instance e3ba9750-03fc-4390-a910-e3b17ca3c163
2018-09-15T18:19:12.44+0530 [STG/0] OUT Cell 850bb788-0cb8-4092-b839-32661cb636dc successfully destroyed container for instance e3ba9750-03fc-4390-a910-e3b17ca3c163