minor #16930 [DependencyInjection] Add missing colon before code example (richardmiller)

This PR was merged into the 6.1 branch.

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[DependencyInjection] Add missing colon before code example

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173f2a9 Add missing colon before code example

Author: javiereguiluz

service_container/autowiring.rst

@@ -546,7 +546,7 @@ in the service configuration. You wire up only the difficult arguments,
 Symfony takes care of the rest.
 
 You can also use the ``#[Autowire]`` parameter attribute to instruct the autowiring
-logic about those arguments:
+logic about those arguments::
 
     // src/Service/MessageGenerator.php
     namespace App\Service;