Don't use latest in helm image tag

[eddycharly]

https://github.com/infracloudio/botkube/blob/16e90962d65b27d874f0a5129e9f42e25d793aeb/helm/botkube/values.yaml#L12

Having latest in helm image tag is dangerous, it breaks with current latest image because of a change in the config yaml file.

[PrasadG193]

Hey @eddycharly,
develop branch contains latest changes under development. So one is not expected to deploy BotKube from develop unless they want to experiment and test changes under development. Ideally, as described in docs (https://www.botkube.io/installation/), one should refer latest release or master branch for development. The helm charts and deploy manifest we have in develop are compatible with latest changes i.e ":latest" branch only. Once we do the release, we tag helm charts and images with the stable tag.

[eddycharly]

Hi @PrasadG193 , that's not true, the helm chart v0.9.1 is using latest (see https://github.com/infracloudio/botkube/releases/download/v0.9.1/helm-chart-botkube-v0.9.1.tgz).

Deploying the chart doesn't work without changing the values right now because of the breaking change in the config file.

[PrasadG193]

I see. If you are talking about default values, then you are right. We should update the release script to overwrite default image tag as well. Thanks

[eddycharly]

Fixed by #259