impr(language): move british spellings to british english mode (@AnnaBuchholz)

[AnnaBuchholz]

Description

I changed the British spellings from the english_25k.json file. I then also deleted a few duplicates. I also added the missing spellings to the british_english.json file.

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impr(language): move british spellings to british english mode (@AnnaBuchholz)

Closes #

[github-actions]

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[yodigi7]

Why was this one removed?

[AnnaBuchholz]

I don't know how to add the fancy line change stuff in this comment, but line 15,020 had fervour which I changed to fervor. Then I saw the duplicate "fervor" on line 20,001 later so I deleted it.