Use the `api_gateway` folder under `treetracker-infrastructure` to deploy the ambassador

[dadiorchen]

• First, please check the current config here to see how do we deploy ambassador, we are using new version of it as described in k3s/emissary.yaml, is this the correct direction to go? Or we should still stick with the definition in treetracerk-infrastructure/api_gateway
• If answer is yes, let's migrate to the api_gateway folder.

[dadiorchen]

I guess there also are some issues in the api_gateway need to be fixed, something like out of date version, dependency problem.

[arnoldcastro5000]

i am adding api_gateway to my local build, @dadiorchen