Symfony Flex issue

[loru88]

When run the command to install composer dependencies

docker run --rm -it --volume $(pwd):/app prooph/composer:7.1 install -o --prefer-dist

I got this error message

Declaration of Symfony\Flex\ParallelDownloader::getRemoteContents($originUrl, $fileUrl, $context) should be compatible with Composer\Util\RemoteFilesystem::getRemoteContents(...

I solved updating Symfony Flex

docker run --rm -it --volume $(pwd):/app prooph/composer:7.1 update symfony/flex --no-scripts

and then tun again the composer dependencies installation.
I think is worth it to insert this update into the installation process

[codeliner]

Had the same problem recently: #36 (comment)

For now it should be solved with #38