I don’t think the UK is very different from the US in this respect. Discrimination based on race, religion, etc is illegal. Asking race, religion, etc as part of the application process is not illegal. Actually, they are supossed to do it (while preventing those details from influencing the hiring process).

The point is that there is a lot of people who do care about race, not just US cops.

https://race.bitc.org.uk/sites/default/files/kcfinder/files/...