minor #13001 composer issue for prefer-lowest has been fixed (dbu)

This PR was submitted for the 4.4 branch but it was merged into the 4.3 branch instead (closes #13001).

Discussion
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composer issue for prefer-lowest has been fixed

The issue composer/composer#5355 has been fixed in composer 1.8 and therefore the workaround is no longer needed.

I have tried on a couple of projects that i don't get errors on travis-ci when removing the instruction.

Once this is in 4.4, it should also be merged to the newer versions.

Commits
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000ebb5 composer issue for prefer-lowest has been fixed

Author: javiereguiluz

bundles/best_practices.rst

@@ -227,8 +227,6 @@ of Symfony and the latest beta release:
         - if ! [ -v "$DEPENDENCIES" ]; then composer require --no-update ${DEPENDENCIES}; fi;
 
     install:
-        # To be removed when this issue will be resolved: https://github.com/composer/composer/issues/5355
-        - if [[ "$COMPOSER_FLAGS" == *"--prefer-lowest"* ]]; then composer update --prefer-dist --no-interaction --prefer-stable --quiet; fi
         - composer update ${COMPOSER_FLAGS} --prefer-dist --no-interaction
         - ./vendor/bin/simple-phpunit install