Guarantee ordering between plugin hooks

[hendrikmakait]

Problem

Currently, there are no ordering guarantees between plugin hooks. In particular, start/setup and close/teardown get executed concurrently for all plugins. This creates problems in some cases (e.g., #8485) and makes it generally harder to reason about things.

Proposed Solution

It would be nice if we could guarantee ordering between the individual plugins. This probably means that we choose their registration order to ensure that the ordering is always the same, e.g. for existing and new workers.

Notes

There are some caveats to this, like non-ordered RPC calls (#7480), that we need to consider.