markdown bug: network args are not separated

[willemneal]

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          Why aren't the options for the network under a separate section like on other commands?

Originally posted by @leighmcculloch in https://github.com/stellar/stellar-cli/pull/1406#discussion_r1689091741

Turns out this applies to all network args in the markdown.

Not sure how important this is, but it would be good if the --help output matched the markdown.