st2web may fail to resolve upstream hosts on IP changes

[winem]

I noticed and issue with the nginx proxy configuration while running some more tests related to #28 (see #28 (comment))

The issue is caused by the fact that nginx resolves the upstream hosts during the startup and caches the response until the next restart. This leads to issues if any of the upstream hosts gets a new IP address due to a restart for example.

I will create a PR to address this issue.

[arm4b]

Turns out creating an issue was too early here as the problem was related to WIP docker-compose #28 (comment) which is not merged yet.

[winem]

I will do a bit more research on this topic.

I created the issue because this may happen in any environment running the st2web container.

Discussion in the community slack for a few more details: https://stackstorm-community.slack.com/archives/CCCNZUGUA/p1589111953039600

I will set the PR to draft for now and will keep this issue open until we know how to fix this for all kind of deployments.

[winem]

A solution is under development and will be part of #28

[arm4b]

Closed via #28