Updates conftest fixtures so they do not autorun

The modules that need to run either bitcoind or the api do now reference to the fixture in the first test that needs it. Since the fixtures are definexd session-wise the rest of the modules will have access to them from that point on.

test/unit/test_block_processor.py

@@ -1,4 +1,5 @@
 import pytest
+import logging
 from os import urandom
 from uuid import uuid4
 from hashlib import sha256
@@ -6,6 +7,8 @@ from binascii import unhexlify
 
 from pisa.block_processor import BlockProcessor
 
+logging.getLogger().disabled = True
+
 APPOINTMENT_COUNT = 100
 TEST_SET_SIZE = 200
 
@@ -25,7 +28,7 @@ def best_block_hash():
     return BlockProcessor.get_best_block_hash()
 
 
-def test_get_best_block_hash(best_block_hash):
+def test_get_best_block_hash(run_bitcoind, best_block_hash):
     # As long as bitcoind is running (or mocked in this case) we should always a block hash
     assert best_block_hash is not None and isinstance(best_block_hash, str)