minor #12026 Update spelling in slash_in_parameter.rst (nasAtchia)

This PR was submitted for the 4.3 branch but it was merged into the 3.4 branch instead (closes #12026).

Discussion
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Update spelling in slash_in_parameter.rst

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Commits
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050affd Update spelling in slash_in_parameter.rst

Author: javiereguiluz

routing/slash_in_parameter.rst

@@ -85,7 +85,7 @@ That's it! Now, the ``{token}`` parameter can contain the ``/`` character.
     use the ``.+`` requirement for the parameters that allow slashes. For example,
     if the pattern is ``/share/{token}.{_format}`` and ``{token}`` allows any
     character, the ``/share/foo/bar.json`` URL will consider ``foo/bar.json``
-    as the token and the format will be empty. This can be solved replacing the
+    as the token and the format will be empty. This can be solved by replacing the
     ``.+`` requirement by ``[^.]+`` to allow any character except dots.
 
 .. note::