Improve generated cli help

[preston-evans98]

Description

Improve the help messages generated by sov-cli.

Before:

$  cargo run generate-transaction accounts update-public-key
error: the following required arguments were not provided:
  <FIELD0>
  <FIELD1>

Usage: main generate-transaction accounts update-public-key <FIELD0> <FIELD1>

For more information, try '--help'.

After:

$ cargo run generate-transaction accounts update-public-key --help
Updates a public key for the corresponding Account. The sender must be in possession of the new key

Usage: main generate-transaction accounts update-public-key <FIELD0> <FIELD1>

Arguments:
  <FIELD0>  The new public key
  <FIELD1>  A valid signature from the new public key

Options:
  -h, --help  Print help

[codecov]

Codecov Report

Merging #581 (e0887f6) into nightly (3835042) will increase coverage by 0.0%.
The diff coverage is 50.0%.

❗ Current head e0887f6 differs from pull request most recent head faa7480. Consider uploading reports for the commit faa7480 to get more accurate results

Files Changed	Coverage Δ
...em/module-implementations/sov-accounts/src/call.rs	72.4% <0.0%> (-2.6%)	⬇️
module-system/sov-modules-macros/src/cli_parser.rs	83.3% <100.0%> (+0.1%)	⬆️

... and 6 files with indirect coverage changes