Key generation overwrite previous key even if --commit not present

[disk91]

The helium_cli env generate-keypair --help says

...
--commit                         overwrite <out_file> if it already exists
...

But helium_cli env generate-keypair has directly generated a keyfile overwritting a production key :(

It would be great to have this --commit option required for overwritting, initial creation may work without this option.