minor #20557 [Doctrine] Use PDO constants in YAML configuration example (phansys)

This PR was merged into the 7.1 branch.

Discussion
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[Doctrine] Use PDO constants in YAML configuration example

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Commits
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1960c77 [Doctrine] Use PDO constants in YAML configuration example

Author: javiereguiluz

reference/configuration/doctrine.rst

@@ -483,12 +483,12 @@ set up the connection using environment variables for the certificate paths:
                 server_version: '8.0.31'
                 driver: 'pdo_mysql'
                 options:
-                    # SSL private key (PDO::MYSQL_ATTR_SSL_KEY)
-                    1007: '%env(MYSQL_SSL_KEY)%'
-                    # SSL certificate (PDO::MYSQL_ATTR_SSL_CERT)
-                    1008: '%env(MYSQL_SSL_CERT)%'
-                    # SSL CA authority (PDO::MYSQL_ATTR_SSL_CA)
-                    1009: '%env(MYSQL_SSL_CA)%'
+                    # SSL private key
+                    !php/const 'PDO::MYSQL_ATTR_SSL_KEY': '%env(MYSQL_SSL_KEY)%'
+                    # SSL certificate
+                    !php/const 'PDO::MYSQL_ATTR_SSL_CERT': '%env(MYSQL_SSL_CERT)%'
+                    # SSL CA authority
+                    !php/const 'PDO::MYSQL_ATTR_SSL_CA': '%env(MYSQL_SSL_CA)%'
 
     .. code-block:: xml