fix create build users action description

[mjgallag]

Description

UID range start is off by 1 in action description:
* Create build users (UID 300-332) and group (GID 30000)
* Create build users (UID 301-332) and group (GID 30000)

Checklist

• Formatted with cargo fmt
• Built with nix build
• Ran flake checks with nix flake check
• Added or updated relevant tests (leave unchecked if not applicable)
• Added or updated relevant documentation (leave unchecked if not applicable)
• Linked to related issues (leave unchecked if not applicable)

Validating with install.determinate.systems

If a maintainer has added the upload to s3 label to this PR, it will become available for installation via install.determinate.systems:

curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix/pr/$PR_NUMBER | sh -s -- install

[Hoverbear]

Thanks!!!

[Hoverbear]

😅 It seems some changes at our org-level have disabled force merging and we had a job that won't complete for folks who aren't maintainers.

Extremely unfortunate. We need to make some tweaks.

In the meantime, I'll re-create this PR and reference this one. Sorry about that.