minor #16133 [Doctrine] Update URL for DoctrineExtensions (phansys)

This PR was merged into the 4.4 branch.

Discussion
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[Doctrine] Update URL for DoctrineExtensions

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Commits
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bcb2dd5 Update URL for DoctrineExtensions

Author: javiereguiluz

doctrine.rst

@@ -54,7 +54,7 @@ The database connection information is stored as an environment variable called
 
     # to use postgresql:
     # DATABASE_URL="postgresql://db_user:[email protected]:5432/db_name?serverVersion=11&charset=utf8"
-    
+
     # to use oracle:
     # DATABASE_URL="oci8://db_user:[email protected]:1521/db_name"
 
@@ -923,5 +923,5 @@ Learn more
 .. _`Doctrine screencast series`: https://symfonycasts.com/screencast/symfony-doctrine
 .. _`API Platform`: https://api-platform.com/docs/core/validation/
 .. _`PDO`: https://www.php.net/pdo
-.. _`available Doctrine extensions`: https://github.com/Atlantic18/DoctrineExtensions
+.. _`available Doctrine extensions`: https://github.com/doctrine-extensions/DoctrineExtensions
 .. _`StofDoctrineExtensionsBundle`: https://github.com/stof/StofDoctrineExtensionsBundle