This prevents shared workers from stalling upon restart.
We receive `Inspector.targetCrashed` and
`Inspector.targetReloadedAfterCrash` events that assume
`Runtime.runIfWaitingForDebugger` from any attached client. It is easier
and more stable to just detach from shared workers, because we do not
inspect them.
For service workers, we should actually issue
`Runtime.runIfWaitingForDebugger` in such cases, because we attach to
them.
Fixes#18932.
