Remove instrumentation key when clearing project configurator connection string to allow re-onboarding
Problem to solve
When a project is configured to point at a BYOC provider (configurator connection string, collector host, cubejs etc) and has completed the onboarding flow (e.g. the project has an instrumentation_key), it is not possible for the project to remove those settings and switch back to using the instance configuration.
Currently, if they change their configurator connection string, the instrumentation_key is removed, allowing re-onboarding to the new configurator. But when removing the connection string, the instrumentation_key remains. This puts the project into a strange state where it is successfully onboarded, but none of the product analytics features will work.
Proposed solution
Update the code here to also remove the instrumentation_key when a connnection string is removed.