fix(cmd): add notice when using --ledger with Ethereum HD path

[lumtis]

Description

Add a notice to quickly figure out the issue when using --ledger with default HD path.

I realized that injecting logic at runtime for an existing command is non-trivial without a fork or wrap (which we don't want for this fix).
I instead added a notice below the execution if the error is cannot set custom bip32 path with ledge

$zetacored keys add testledger --ledger --account 0
Error: cannot set custom bip32 path with ledger
Usage:
  <appd> keys add <name> [flags]

Flags:
      --account uint32           Account number for HD derivation (less than equal 2147483647)
      --algo string              Key signing algorithm to generate keys for (default "eth_secp256k1")
      --coin-type uint32         coin type number for HD derivation (default 118)
      --dry-run                  Perform action, but don't add key to local keystore
      --hd-path string           Manual HD Path derivation (overrides BIP44 config) (default "m/44'/60'/0'/0/0")
  -h, --help                     help for add
      --index uint32             Address index number for HD derivation (less than equal 2147483647)
  -i, --interactive              Interactively prompt user for BIP39 passphrase and mnemonic
      --ledger                   Store a local reference to a private key on a Ledger device
      --multisig strings         List of key names stored in keyring to construct a public legacy multisig key
      --multisig-threshold int   K out of N required signatures. For use in conjunction with --multisig (default 1)
      --no-backup                Don't print out seed phrase (if others are watching the terminal)
      --nosort                   Keys passed to --multisig are taken in the order they're supplied
      --pubkey string            Parse a public key in JSON format and saves key info to <name> file.
      --recover                  Provide seed phrase to recover existing key instead of creating

Global Flags:
      --keyring-backend string   Select keyring's backend (os|file|test) (default "os")
      --keyring-dir string       The client Keyring directory; if omitted, the default 'home' directory will be used
      --log_format string        The logging format (json|plain) (default "plain")
      --log_level string         The logging level (trace|debug|info|warn|error|fatal|panic) (default "info")
      --output string            Output format (text|json) (default "text")
      --trace                    print out full stack trace on errors

*****************************************************************************
* note: --ledger flag can't be used with Ethereum HD path (used by default)
* use --hd-path="" in the command to use Cosmos HD path
*****************************************************************************

Closes: #1284

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Include instructions and any relevant details so others can reproduce.

• Tested CCTX in localnet
• Tested in development environment
• Go unit tests
• Go integration tests
• Tested via GitHub Actions

Checklist:

• I have added unit tests that prove my fix feature works

[kevinssgh]

Looks good