Refactor: Improve UK Phone number false failure hit-rate

[luke-hill]

This PR aims to improve the false failure hit-rate for UK Phone numbers. Partially alleviates #3135

Additional information

Reference from Ofcom drama list: https://www.ofcom.org.uk/phones-and-broadband/phone-numbers/numbers-for-drama

Checklist

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[thdaraujo]

Very nice, thank you! The commit message has enough context, so no need for these comments.