add new migrations file

Author: jewei1997

x/evm/migrations/migrate_eip_1559_max_base_fee.go

@@ -0,0 +1,14 @@
+package migrations
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/sei-protocol/sei-chain/x/evm/keeper"
+	"github.com/sei-protocol/sei-chain/x/evm/types"
+)
+
+func MigrateEip1559MaxFeePerGas(ctx sdk.Context, k *keeper.Keeper) error {
+	keeperParams := k.GetParamsIfExists(ctx)
+	keeperParams.MaximumFeePerGas = types.DefaultParams().MaximumFeePerGas
+	k.SetParams(ctx, keeperParams)
+	return nil
+}