Backport: Do not print the Pulp CLI result after RPM uploads

What does this MR do and why?

Backport of !9972 (merged) to 19-4-stable.

Run the RPM upload with pulp --format none, so the pulp CLI does not print the result as JSON. With --no-publish (PULP_CLI_PUBLISH=false, which is set on dev.gitlab.org), the result is the new package, and its JSON lists every file in the package. For gitlab-fips this is more than 4 MB, so the upload job log reached the 4 MB limit and GitLab stopped collecting it after the first upload. This backport keeps the release pipeline logs of this stable branch complete.

Related to gitlab-com/gl-infra/delivery#22495 (closed)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
• The original MR has been deployed to GitLab.com (not applicable for documentation or spec changes).
• This MR has a severity label assigned (if applicable).

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