deploy:jar is not available in heroku cli by default.

[berndhopp]

on this page the command

heroku deploy:jar ...

gave me an error response saying that deploy:jar is not supported. I needed to run

heroku plugins:install java

first in order to be able to call deploy:jar.

It should also be noted that vaadin apps can be deployed to heroku with CI/CD-Pipelines, as long as the -Pproduction maven flag is set via the CLI, as below. This should be the first option for heroku deployment IMHO.

heroku config:set MAVEN_CUSTOM_OPTS="-Pproduction"