@adrian, the reason is: CI/CD deployment. Steps:
Creating a new migration via RockMigrations in git (module is included in whole website git)
Updating the module version in git
Pushing the changes
CI/CD is automatically building and creating a new docker container
With start of the container, refreshing should be done automatically which then automatically executes the migration
My problem: I can automate the refreshing via php cli, but the execution of the migrations is only handled when calling the website via a GET call. When pushing the refresh button in processWire backend, refreshing AND migration upgrading is executed.