Fix --genesis-file descriptions in ash avax blockchain create -h

[leopaul36]

ash avax blockchain create -h
Create a new blockchain

Usage: ash avalanche blockchain create [OPTIONS] --subnet-id <SUBNET_ID> --private-key <PRIVATE_KEY> <NAME>

Arguments:
  <NAME>  Blockchain name

Options:
  -t, --vm-type <VM_TYPE>            Blockchain VM type [default: SubnetEVM]
  -i, --vm-id <VM_ID>                Blockchain VM ID [default: spePNvBxaWSYL2tB5e2xMmMNBQkXMN8z2XEbz1ML2Aahatwoc]
  -n, --network <NETWORK>            Avalanche network [env: AVALANCHE_NETWORK=local] [default: mainnet]
  -g, --genesis-str <GENESIS_STR>    Blockchain genesis data string (hex encoded)
  -j, --json                         Output in JSON format [env: ASH_JSON=]
  -c, --config <CONFIG>              Path to the configuration file [env: ASH_CONFIG=/etc/avalanche/ash-cli/conf/default.yml]
  -f, --genesis-file <GENESIS_FILE>  Path to a JSON file containing the blockchain genesis data (generated with `ash avalanche vm encode-genesis`)
  -s, --subnet-id <SUBNET_ID>        Subnet ID to create the blockchain on
  -p, --private-key <PRIVATE_KEY>    Private key to sign the transaction with (must be a control key) [env: AVALANCHE_PRIVATE_KEY=]
  -e, --key-encoding <KEY_ENCODING>  Private key format [env: AVALANCHE_KEY_ENCODING=] [default: cb58] [possible values: cb58, hex]
  -w, --wait                         Whether to wait for transaction acceptance
  -h, --help                         Print help
  -V, --version                      Print version

genesis-file is not a JSON file