added fr_FR.UTF-8 locale

Dockerfile

@@ -201,7 +201,7 @@ RUN apt-get update \
         locales \
         ssl-cert \
         tzdata \
-    && locale-gen en_US.UTF-8 \
+    && locale-gen en_US.UTF-8 fr_FR.UTF-8 \
     && ln -snf "/usr/share/zoneinfo/${TZ}" /etc/localtime \
     && echo "${TZ}" > /etc/timezone \
     && rm -rf /var/lib/apt/lists/*