test: drop interface_ipc_mining.py

Author: Sjors

test/functional/interface_ipc_mining.py

@@ -359,7 +359,6 @@
     'feature_help.py',
     'feature_framework_startup_failures.py',
     'feature_shutdown.py',
-    'interface_ipc_mining.py',
     'wallet_migration.py',
     'p2p_ibd_txrelay.py',
     'p2p_seednode.py',