Unique (HelmChart) Artifact URLs

[hiddeco]

At present, the Artifact file name (and thus URL) is composed out of just chart metadata. Due to the way Helm chart builds are not reproducable, this may cause issues on the consumer side when a chart is rebuild due to e.g. a controller restart, but advertised on the same URL. As this causes a mismatch in the checksum calculation.

Given a checksum mismatch error triggers a lot more red flags for an operator than a temporary "404 not found", it would be good idea to add some randomness to the advertised Artifact URL.

To my knowledge, only HelmCharts are affected by this, as other resources strip data (e.g. timestamps).