minor #20052 Remove Doctrine mappings YML from documentation (Cosmin Sandu, cosminsandu)

This PR was merged into the 5.4 branch.

Discussion
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Remove Doctrine mappings YML from documentation

#20050

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Commits
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d09a5ba issues/20050 Remove Doctrine mappings YML from documentation try to fix CI
a7d1540 Update reference/configuration/doctrine.rst
1a22c51 issues/20050 Remove Doctrine mappings YML from documentation #20050

Author: javiereguiluz

.doctor-rst.yaml

@@ -109,5 +109,6 @@ whitelist:
         - '.. versionadded:: 3.6' # MonologBundle
         - '.. versionadded:: 3.8' # MonologBundle
         - '.. versionadded:: 3.5' # Monolog
+        - '.. versionadded:: 3.0' # Doctrine ORM
         - '.. _`a feature to test applications using Mercure`: https://github.com/symfony/panther#creating-isolated-browsers-to-test-apps-using-mercure-or-websocket'
         - '..  End to End Tests (E2E)'

reference/configuration/doctrine.rst

@@ -269,9 +269,14 @@ you can control. The following configuration options exist for a mapping:
 ........
 
 One of ``annotation`` (for PHP annotations; it's the default value),
-``attribute`` (for PHP attributes), ``xml``, ``yml``, ``php`` or
+``attribute`` (for PHP attributes), ``xml``, ``php`` or
 ``staticphp``. This specifies which type of metadata type your mapping uses.
 
+.. versionadded:: 3.0
+
+    The ``yml`` mapping configuration is deprecated and will be removed in doctrine/orm 3.0.
+
+
 See `Doctrine Metadata Drivers`_ for more information about this option.
 
 ``dir``