github-runner: Labels are not passed correctly

[srid]

After #1055, the github-runner's configure script contains bash that sets labels like this:

--labels "'sambar,aarch64-darwin,x86_64-darwin'"

Note the double quotation above.

PR #1055 did add the double quotes so I'm guessing that's the trigger?

When passing --labels like this, GitHub will consider that inner quote (') as being part of the label text, leading to:

Ref: juspay/github-nix-ci#10