Testing against different versions of Redash

[b4handjr]

So as seen in PR #73, the redash-ui-test suite runs against the latest tag. This time there were some breaking changes introduced in the 5.0 beta that requires some changes to how our tests run. This has made me wonder how we should handle our testing.

We want to keep the upstream tests running but to do that, we need to make sure our tests can run against the current latest as well as the current beta build.

[b4handjr]

Doing some research it seems the docker builds aren't kept quite up to date, and the tag name changes too. We would have to pull current redash master and build a docker image of that to be at the same point as the upstream integration-tests.

[jezdez]

Hm, that sounds like a good plan of action, being able to test both, the "latest" release that upstream has made, as well as the current "development" version, is definitely a worthwhile goal. 👍

[hackebrot]

This issue is a duplicate of #6. I'll close the other one as it hasn't seen any comments.