minor #6530 [DependencyInjection] Unquote services FQCN in parent-services examples (chalasr)

This PR was merged into the 2.3 branch.

Discussion
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[DependencyInjection] Unquote services FQCN in parent-services examples

Same as #6529 on a older chapter, with some incoherences fixed (sometimes double quotes, simple quotes, and, as it should be, no quotes).

Commits
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e39278e [DependencyInjection] Unquote services FQCN in parent-services examples

Author: xabbuh

components/dependency_injection/parentservices.rst

@@ -67,7 +67,7 @@ The service config for these classes would look something like this:
                     - [setEmailFormatter, ['@my_email_formatter']]
 
             greeting_card_manager:
-                class: 'GreetingCardManager'
+                class: GreetingCardManager
                 calls:
                     - [setMailer, ['@my_mailer']]
                     - [setEmailFormatter, ['@my_email_formatter']]
@@ -196,11 +196,11 @@ a parent for a service.
                     - [setEmailFormatter, ['@my_email_formatter']]
 
             newsletter_manager:
-                class:  "NewsletterManager"
+                class:  NewsletterManager
                 parent: mail_manager
 
             greeting_card_manager:
-                class:  "GreetingCardManager"
+                class:  GreetingCardManager
                 parent: mail_manager
 
     .. code-block:: xml
@@ -324,13 +324,13 @@ to the ``NewsletterManager`` class, the config would look like this:
                     - [setEmailFormatter, ['@my_email_formatter']]
 
             newsletter_manager:
-                class:  'NewsletterManager'
+                class:  NewsletterManager
                 parent: mail_manager
                 calls:
                     - [setMailer, ['@my_alternative_mailer']]
 
             greeting_card_manager:
-                class:  'GreetingCardManager'
+                class:  GreetingCardManager
                 parent: mail_manager
 
     .. code-block:: xml