That is just throughout the core library, not the tests yet. Again, we
simply change over to using our (nearly equivalent?)
`.trionics.collapse_eg()` in place of the already deprecated
`strict_exception_groups=False` flag in the following internals,
- the conc-fan-out tn use in `._discovery.find_actor()`.
- `._portal.open_portal()`'s internal tn used to spawn a bg rpc-msg-loop
task.
- the daemon and "run-in-actor" layered tn pair allocated in
`._supervise._open_and_supervise_one_cancels_all_nursery()`.
The remaining loose-eg usage in `._root` and `._runtime` seem to be
necessary to keep the test suite green?? For the moment these are left
out.
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