CLI install instructions don't work

[walles]

Instructions

https://github.com/zRedShift/mimemagic/blob/5028b726e7cdb453d7bccb8c660ab9f75c488c79/README.md?plain=1#L42-L45

Result

/tmp $ go get github.com/zRedShift/mimemagic/v2/cmd/mimemagic
go: go.mod file not found in current directory or any parent directory.
	'go get' is no longer supported outside a module.
	To build and install a command, use 'go install' with a version,
	like 'go install example.com/cmd@latest'
	For more information, see https://golang.org/doc/go-get-install-deprecation
	or run 'go help get' or 'go help install'.
/tmp [1]$

I'm on go version go1.21.1 darwin/arm64.