Update Dockerfile.apache

contrib/docker/Dockerfile.apache

@@ -5,7 +5,7 @@ ARG COMPOSER_CHECKSUM="67bebe9df9866a795078bb2cf21798d8b0214f2e0b2fd81f2e907a8ef
 
 RUN apt-get update \
  && apt-get install -y --no-install-recommends git gosu \
-      optipng pngquant jpegoptim gifsicle \
+      optipng pngquant jpegoptim gifsicle libpq-dev \
       libfreetype6 libicu-dev libjpeg62-turbo libpng16-16 libxpm4 libwebp6 libmagickwand-6.q16-3 \
       libfreetype6-dev libjpeg62-turbo-dev libpng-dev libxpm-dev libwebp-dev libmagickwand-dev \
  && docker-php-source extract \