This PR changes the functional tests to have a consistent naming scheme:Rename only, except a minor update in doc/functional-tests.md
```
tests for individual RPC methods are named rpc_...
tests for interfaces (REST, ZMQ, RPC features) are named interface_...
tests that explicitly test the p2p interface are named p2p_...
tests for wallet features are named wallet_...
tests for mining features are named mining_...
tests for mempool behaviour are named mempool_...
tests for full features that aren't wallet/mining/mempool are named
feature_...
```
Backport of core PR11774
This is a rename only backport.
There is a test missing from this backport (rpc_deprecated.py) which has
been removed in D2012.
This test should be added again when a new deprecation occurs and named
accordingly.Partial backport of core PR11774 (commit ca6523d)
Depends on D2370