Ensure that tests run with the C.UTF-8 locale
Ensure that tests run with the C.UTF-8 locale

Some database tests depend on the text returned by the SQL client, which
is localized. Forcing the C locale ensures the text gets output in
English.

SoftwareHeritage/swh-web-ui,SoftwareHeritage/swh-web-ui,SoftwareHeritage/swh-web-ui