minor #13459 Document support for Memcached in Docker Compose (fabpot)

This PR was merged into the 3.4 branch.

Discussion
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Document support for Memcached in Docker Compose

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Commits
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dd39018 Document support for Memcached in Docker Compose

Author: javiereguiluz

setup/symfony_server.rst

@@ -286,6 +286,7 @@ Service       Port      Symfony default prefix
 MySQL         3306      ``DATABASE_``
 PostgreSQL    5432      ``DATABASE_``
 Redis         6379      ``REDIS_``
+Memcached     11211     ``MEMCACHED_``
 RabbitMQ      5672      ``RABBITMQ_`` (set user and pass via Docker ``RABBITMQ_DEFAULT_USER`` and ``RABBITMQ_DEFAULT_PASS`` env var)
 Elasticsearch 9200      ``ELASTICSEARCH_``
 MongoDB       27017     ``MONGODB_`` (set the database via a Docker ``MONGO_DATABASE`` env var)