Include .gitlab folder in files checked by renovate

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What does this MR do and why?

this MR updates the default renovate config so that it also checks files located in the .gitlab folder

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

How to set up and validate locally

• run renovate with the new config and see it now also checks yaml files located in the .gitlab folder