chore(metadata): remove access policies metadata, cleanup some labels

[KNiepok]

Description of the change

This PR introduces two changes:

• removes access policies metadata
• creates a consistent way of phrasing labels to avoid similar, duplicated labels

Checklist

Please make sure that the proposed change checks all the boxes below before requesting a review:

• Each new policy has corresponding tests.
• All the tests pass.
• The pull request is opened against the main branch.
• The pull request is no longer marked as a draft.
• You agree to license your contribution under the MIT license to Spacelift (not required for Spacelift employees).

If the proposed change is ready to be merged, please request a review from @spacelift-io/solutions-engineering. Someone will review and merge the pull request.

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Thank you for your contribution! 🙇