go-ncm as a seperate exectuable

[doronz88]

Hi,

I'm the author of pymobiledevice3 , and in the context of what was suggested in doronz88/pymobiledevice3#566 (comment), It would be great to have an additional github action to publish the go-ncm binary seperately, or maybe even make it into its own seperate github repository.

That way, other tools (and my own) could either remotely fetch it as an external asset (which is what I though of) or bundle it altogether with their own tool.