l10n: fr: don't translate "merge" as a parameter

At builtin/checkout.c:1154, merge is a parameter to --conflict=<style>
(git checkout --conflict=merge).

Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>

po/fr.po

diff --git a/po/fr.po b/po/fr.po
index 868514e..55ca387 100644
--- a/po/fr.po
+++ b/po/fr.po
@@ -4545,7 +4545,7 @@
 
 #: builtin/checkout.c:1154
 msgid "conflict style (merge or diff3)"
-msgstr "style de conflit (fusion ou diff3)"
+msgstr "style de conflit (merge (fusion) ou diff3)"
 
 #: builtin/checkout.c:1157
 msgid "do not limit pathspecs to sparse entries only"