Update translation files

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Translation: RoR Player/Tune description: no-border-bossa
Translate-URL: https://hosted.weblate.org/projects/ror-player/tune-description-no-border-bossa/

assets/tuneDescriptions/no-border-bossa/fr.md

@@ -1,6 +1,6 @@
 **Sign:** interlock your hands like a fence and then open it.
 
-## Background
+## Contexte
 
 **Name:** Bossa Nova is a Brazilian style of music that developed out of Samba,
 which usually involves a guitar and a singer on top of the characteristic Bossa