minor #6190 Fix redundant command line sample (sylozof)

This PR was merged into the 2.3 branch.

Discussion
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Fix redundant command line sample

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets | #6189

Removed option ``--with-dependencies`` from the first command line example for composer upgrade.

Commits
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c8618e1 Update major_version.rst

Author: xabbuh

cookbook/upgrade/major_version.rst

@@ -134,7 +134,7 @@ Next, use Composer to download new versions of the libraries:
 
 .. code-block:: bash
 
-    $ composer update --with-dependencies symfony/symfony
+    $ composer update symfony/symfony
 
 .. include:: /cookbook/upgrade/_update_dep_errors.rst.inc