minor #21327 [Runtime] Add support for JSON encoded APP_RUNTIME_OPTIONS value (VincentLanglet)

This PR was merged into the 7.4 branch.

Discussion
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[Runtime] Add support for JSON encoded APP_RUNTIME_OPTIONS value

Closes #21323

Commits
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26fea4c Add support for JSON encoded APP_RUNTIME_OPTIONS value

Author: javiereguiluz

components/runtime.rst

@@ -302,16 +302,23 @@ Using Options
 ~~~~~~~~~~~~~
 
 Some behavior of the Runtimes can be modified through runtime options. They
-can be set using the ``APP_RUNTIME_OPTIONS`` environment variable::
+can be set using the ``APP_RUNTIME_OPTIONS`` environment variable as an array
+or a JSON encoded value::
 
     $_SERVER['APP_RUNTIME_OPTIONS'] = [
         'project_dir' => '/var/task',
     ];
+    // Which is the same than
+    // $_SERVER['APP_RUNTIME_OPTIONS'] = '{"project_dir":"\/var\/task"}';
 
     require_once dirname(__DIR__).'/vendor/autoload_runtime.php';
 
     // ...
 
+.. versionadded:: 7.4
+
+    The support for JSON encoded APP_RUNTIME_OPTIONS value was introduced in Symfony 7.4.
+
 You can also configure ``extra.runtime`` in ``composer.json``:
 
 .. code-block:: json