Added some examples to the "services as parameters" section
Removed the file path comments because this doc is for the component and it should not make any reference to Symfony
minor #3641 Added some examples to the "services as parameters" section (javiereguiluz)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #3641).

Discussion
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Added some examples to the "services as parameters" section

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | yes
| Applies to    | 2.3+
| Fixed tickets | no

Commits
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745f3a6 Removed the file path comments because this doc is for the component and it should not make any reference to Symfony
6abb310 Added some examples to the "services as parameters" section