UX: remove flag --chapel

[zzzckck]

Rationale

network can be read from the config.toml file, seems no need to add this extra flag.

Implementation

NA

[buddh0]

Rationale

network can be read from the config.toml file, seems no need to add this extra flag.

Implementation

NA

some commands not support using config.toml
such as importHistory

other few scenarios, some actions happened before reading config.toml
such as func prepare(ctx *cli.Context)

and in addition, '--chapel' is totally following the geth

	NetworkIdFlag = &cli.Uint64Flag{
		Name:     "networkid",
		Usage:    "Explicitly set network id (integer)(For testnets: use --goerli, --sepolia, --holesky instead)",
		Value:    ethconfig.Defaults.NetworkId,
		Category: flags.EthCategory,
	}

I think we can support removing '--chapel' and read the networkId from config.toml when we do a sync,
but not removing --chapel totally.