Make the completion compatible with `fish` shell

[tamdaz]

Description

In the “Shell Completion” doc section, completion is only available for two shells: zsh and bash. It may be useful to make completion compatible with the fish shell.

If you have any questions about this shell, please feel free to ask. I often use fish.

Source(s)

• https://tempestphp.com/3.x/essentials/console-commands#shell-completion

[xHeaven]

@tamdaz I've landed a PR for fish completion support, I'd appreciate if you'd take a look at it and share your feedback. I've tested it myself and looks fine, but maybe there's something I've missed. Thanks!