Found a chicken and egg problem using pulumi on the CI (maybe due to using yarn 3). Clean machine, yarn install, shows the following error message. Which is logical since pulumi only gets installed a lot later in the build process using the github action. The pulumi run then fails since the plugins are not installed.

I may be on the wrong track but try yarn add @pulumi/pulumi

that does not install the cli though. this is a CI issue, so in general people would not notice