minor #12178 Use https for xsd (OskarStark)

This PR was merged into the 4.3 branch.

Discussion
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Use https for xsd

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Commits
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bc76dbc Use https for xsd

Author: OskarStark

http_cache/ssi.rst

@@ -64,9 +64,9 @@ First, to use SSI, be sure to enable it in your application configuration:
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xmlns:framework="http://symfony.com/schema/dic/symfony"
             xsi:schemaLocation="http://symfony.com/schema/dic/services
-                http://symfony.com/schema/dic/services/services-1.0.xsd
+                https://symfony.com/schema/dic/services/services-1.0.xsd
                 http://symfony.com/schema/dic/symfony
-                http://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
+                https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
 
             <framework:config>
                 <framework:ssi enabled="true"/>