MERGE FIX: Prevent mainnet unit tests from thinking they have signed blocks after custom tests

Author: instagibbs

src/chainparams.cpp

@@ -147,6 +147,7 @@ class CMainParams : public CChainParams {
         enforce_pak = false;
         multi_data_permitted = false;
         consensus.has_parent_chain = false;
+        g_signed_blocks = false;
 
         /**
          * The message start string is designed to be unlikely to occur in normal data.