[CI] Try to make composer run

RUN set -e \

      && apt -y update \

      && apt -y upgrade \

      && apt -y install --no-install-recommends --no-install-suggests ca-certificates git \

      && apt -y install --no-install-recommends --no-install-suggests ca-certificates composer git \

      && apt -y autoremove \

      && apt clean \

      && rm -rf /var/lib/apt/lists/*

# install plugins using composer

RUN set -e \

      /usr/bin/composer \

RUN set -e && /usr/bin/composer \

      --working-dir=/usr/src/roundcubemail/ \

      --prefer-dist \

      --prefer-stable \

      --update-no-dev \

      --no-interaction \

      --optimize-autoloader \

      --quiet \

      require \

        johndoh/contextmenu