fix(translations): regularise the capitalisation of 'CSV' in en localisation

[stuartyeates]

SUMMARY

Regularise capitalisation of 'CSV' in en localisation. Capitialisation was previous a mixture of 'csv', 'Csv' and 'CSV'

Filenames and function names have not been touched.

Translations I don't speak have not been touched (but show similar issues).

ADDITIONAL INFORMATION

• [ x] Changes UI

[github-actions]

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[codecov]

Codecov Report

Merging #24440 (9e134ea) into master (db65b74) will not change coverage.
The diff coverage is n/a.

❗ Current head 9e134ea differs from pull request most recent head afcab0c. Consider uploading reports for the commit afcab0c to get more accurate results

@@           Coverage Diff           @@
##           master   #24440   +/-   ##
=======================================
  Coverage   68.93%   68.93%           
=======================================
  Files        1904     1904           
  Lines       73878    73878           
  Branches     8119     8119           
=======================================
  Hits        50927    50927           
  Misses      20840    20840           
  Partials     2111     2111           

Flag	Coverage Δ
hive	53.94% <ø> (ø)
mysql	79.25% <ø> (ø)
postgres	79.34% <ø> (ø)
presto	53.86% <ø> (ø)
python	83.33% <ø> (ø)
sqlite	77.83% <ø> (ø)
unit	54.64% <ø> (ø)

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