Optionally kill Worker when PipInstall plugin fails to install something

Hi team,

Currently if `PipInstall` plugin fails to install something for whatever reason in a worker, the worker will continue to run tasks. However, in our use case we don't want to run any tasks if PipInstall plugin failed.

Currently we can achieve this by overriding `_InstallWorkerPlugin` but we prefer not to access private classes.

We understand that `PipInstall` "is primarily intended for experimentation and debugging", but in our use case we can't include the library in the image. It would be very helpful if `PipInstall` can optionally kill Worker when it fails.

Thanks in advance