op-service: Add omitempty to EIP1559Params (#12582)

* op-deployer: Add support for inspecting l2 semvers

* goimports

* add factory targets

* op-service: Add omitempty to EIP1559Params

These parameters are only valid for Holocene, and cause errors during unmarshaling on older op-node versions.

op-service/eth/types.go

@@ -419,7 +419,7 @@ type SystemConfig struct {
 	// EIP1559Params contains the Holocene-encoded EIP-1559 parameters. This
 	// value will be 0 if Holocene is not active, or if derivation has yet to
 	// process any EIP_1559_PARAMS system config update events.
-	EIP1559Params Bytes8 `json:"eip1559Params"`
+	EIP1559Params Bytes8 `json:"eip1559Params,omitempty"`
 	// More fields can be added for future SystemConfig versions.
 }