minor #12044 Useless code in an example (makmaoui)

This PR was submitted for the 4.3 branch but it was merged into the 3.4 branch instead (closes #12044).

Discussion
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Useless code in an example

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Commits
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13c2398 Useless code in an example

Author: OskarStark

components/yaml.rst

@@ -302,8 +302,6 @@ Similarly you can use ``DUMP_EXCEPTION_ON_INVALID_TYPE`` when dumping::
     $data = new \stdClass(); // by default objects are invalid.
     Yaml::dump($data, 2, 4, Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE); // throws an exception
 
-    echo $yaml; // { foo: bar }
-
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