add unicode locale generation to Dockerfile

before the change, unicode characters were displayed in console as question marks

Dockerfile

@@ -83,6 +83,12 @@ RUN mkdir -p ${DATA_PATH}/Chunky/tasks && \
     ln -sf ${DATA_PATH}/Chunky/tasks \
         ${CONFIG_PATH}/plugins/Chunky/tasks
 
+# Generate unicode locale so that cyrillic characters display properly
+RUN apt-get update -y && apt-get install -y locales && \
+    echo en_US.UTF-8 UTF-8 > /etc/locale.gen && \
+    dpkg-reconfigure --frontend=noninteractive locales
+ENV LANG en_US.UTF-8
+
 
 VOLUME ${DATA_PATH}