Check ticketing plugins against current versions

The documentation currently states that Jira custom fields in the ticketing plugin have been tested against Jira 6.3.15. Since we are now at Jira 8.14, it would be good to test these custom fields and update the docs/plugin to reflect any updates.

Remedy plugin lists currently supported product versions as 7.6.04, now at 9.0+

Flows chapter on setup, refers to having Helm 2.0.0 or greater installed. Verify that example works with current Helm version.