minor #12710 Add Blackfire Docker support for the local web server (fabpot)

This PR was merged into the 3.4 branch.

Discussion
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Add Blackfire Docker support for the local web server

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eb9a827 Add Blackfire Docker support for the local web server

Author: OskarStark

setup/symfony_server.rst

@@ -305,7 +305,8 @@ Elasticsearch 9200      ``ELASTICSEARCH_``
 MongoDB       27017     ``MONGODB_`` (set the database via a Docker ``MONGO_DATABASE`` env var)
 Kafka         9092      ``KAFKA_``
 Mailcatcher   1025/1080 ``MAILER_``
-              25/80
+              or 25/80
+Blackfire     8707      ``BLACKFIRE_``
 ============= ========= ======================
 
 You can open web management interfaces for the services that expose them: