doc: add note about AsyncResource for Worker pooling
When implementing a pool for Worker threads, the correlation between posting tasks and getting their results may get lost, depending on the implementation.
The AsyncResource
API is the primary way to solve that issue,
so link it from the recommendation in the worker docs.
(This was brought up at the collaborator summit in Berlin.)
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
documentation is changed or added -
commit message follows commit guidelines