db_lmdb: move spammy "not found in db" message to TRACE

These are functions that check whether a tx is in the db, so whether
it is there or not is really not interesting, and it seems to scare
people from time to time

src/blockchain_db/lmdb/db_lmdb.cpp

@@ -3001,7 +3001,7 @@ bool BlockchainLMDB::tx_exists(const crypto::hash& h) const
 
   if (! tx_found)
   {
-    LOG_PRINT_L1("transaction with hash " << epee::string_tools::pod_to_hex(h) << " not found in db");
+    LOG_PRINT_L3("transaction with hash " << epee::string_tools::pod_to_hex(h) << " not found in db");
     return false;
   }
 
@@ -3032,7 +3032,7 @@ bool BlockchainLMDB::tx_exists(const crypto::hash& h, uint64_t& tx_id) const
   bool ret = false;
   if (get_result == MDB_NOTFOUND)
   {
-    LOG_PRINT_L1("transaction with hash " << epee::string_tools::pod_to_hex(h) << " not found in db");
+    LOG_PRINT_L3("transaction with hash " << epee::string_tools::pod_to_hex(h) << " not found in db");
   }
   else if (get_result)
     throw0(DB_ERROR(lmdb_error("DB error attempting to fetch transaction from hash", get_result).c_str()));