Set COMPOSER_MEMORY_LIMIT to -1
Set COMPOSER_MEMORY_LIMIT to -1

Composer commands are run inside a PHP runner. Their memory does not
need the constrains as the application itself needs.

By setting the `COMPOSER_MEMORY_LIMIT` environment variable explicitly
to `-1`, Composer itself modifies the memory limit on-the-fly, only to
affect Composer commands.

This allows running `composer update` on more memory intensive
dependency graphs, without sacrificing the constraints througout the
rest of the project.

JeroenBoersma/docker-compose-development,JeroenBoersma/docker-compose-development