func(cfg): add saveCancelAllUnfreezeV2Details switch description to the configuration file

Author: yanghang8612

framework/src/main/resources/config.conf

@@ -611,6 +611,9 @@ vm = {
   # Indicates whether the node stores featured internal transactions, such as freeze, vote and so on
   # saveFeaturedInternalTx = false
 
+  # Indicates whether the node stores the details of the internal transactions generated by the CANCELALLUNFREEZEV2 opcode, such as bandwidth/energy/tronpower cancel amount.
+  # saveCancelAllUnfreezeV2Details = false
+
   # In rare cases, transactions that will be within the specified maximum execution time (default 10(ms)) are re-executed and packaged
   # longRunningTime = 10