fix composer auth var

Dockerfile

@@ -5,7 +5,6 @@ RUN apt-get update
 
 # Install composer
 ENV COMPOSER_HOME "/home/www-data/.composer"
-ENV COMPOSER_AUTH "{ \"http-basic\": { \"php-packages.chargemap.com\": { \"username\": \"chargemap\", \"password\": \"Fy6Rys[WYNpzVkh;\" } } }"
 RUN mkdir -p $COMPOSER_HOME && chmod -R 777 $COMPOSER_HOME && curl -sS https://getcomposer.org/installer | php \
   && chmod +x composer.phar && mv composer.phar /usr/local/bin/composer