Only require credit card data if shared runners are enabled

What does this MR do?

Related to https://gitlab.com/gitlab-org/gitlab/-/issues/330751

While we are rolling out the credit card requirement to run a pipeline for new users on Free plan, the requirement has slightly changed. We should not ask for credit card if the project has shared runners disabled, meaning the project uses private runners: https://gitlab.com/gitlab-org/gitlab/-/issues/330751#note_575286916.

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