In this tutorial https://www.pulumi.com/docs/tutorials/aws/aws-ts-ec2-provisioners/ what is the significance of the final two dashes after each cat line? Are they necessary or is that a typo?

$ cat rsa.pub | pulumi config set publicKey --
$ cat rsa | pulumi config set privateKey --secret --

I think it's a bash thing to indicate "end of arguments". IME, they're not strictly necessary, but a good practice.