refactor: Don't use global chainparams in chainstatemanager method

The chainstatemanager m_options.chainparams member variable gets its
value from the global chainparams in init.cpp. This allows
validation.cpp to only include the the kernel chainparams file.

src/validation.cpp

@@ -10,7 +10,6 @@
 
 #include <arith_uint256.h>
 #include <chain.h>
-#include <chainparams.h>
 #include <checkqueue.h>
 #include <consensus/amount.h>
 #include <consensus/consensus.h>
@@ -5430,7 +5429,7 @@ SnapshotCompletionResult ChainstateManager::MaybeCompleteSnapshotValidation(
     CCoinsViewDB& ibd_coins_db = m_ibd_chainstate->CoinsDB();
     m_ibd_chainstate->ForceFlushStateToDisk();
 
-    auto maybe_au_data = ExpectedAssumeutxo(curr_height, ::Params());
+    auto maybe_au_data = ExpectedAssumeutxo(curr_height, m_options.chainparams);
     if (!maybe_au_data) {
         LogPrintf("[snapshot] assumeutxo data not found for height " /* Continued */
             "(%d) - refusing to validate snapshot\n", curr_height);