internal/ethapi: reject non-replay-protected txs over RPC (#22339)

This PR prevents users from submitting transactions without EIP-155 enabled. This behaviour can be overridden by specifying the flag --rpc.allow-unprotected-txs=true.

node/config.go

@@ -191,6 +191,9 @@ type Config struct {
 	staticNodesWarning     bool
 	trustedNodesWarning    bool
 	oldGethResourceWarning bool
+
+	// AllowUnprotectedTxs allows non EIP-155 protected transactions to be send over RPC.
+	AllowUnprotectedTxs bool `toml:",omitempty"`
 }
 
 // IPCEndpoint resolves an IPC endpoint based on a configured value, taking into