minor #5609 Add a missing backtick (fabschurt)

This PR was merged into the 2.3 branch.

Discussion
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Add a missing backtick

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | >= 2.3
| Fixed tickets | N/A

Commits
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740e58d Add a missing backtick

create_framework/templating.rst

@@ -173,7 +173,7 @@ framework does not need to be modified in any way, just create a new
 The ``is_leap_year()`` function returns ``true`` when the given year is a leap
 year, ``false`` otherwise. If the year is ``null``, the current year is
 tested. The controller is simple: it gets the year from the request
-attributes, pass it to the `is_leap_year()`` function, and according to the
+attributes, pass it to the ``is_leap_year()`` function, and according to the
 return value it creates a new Response object.
 
 As always, you can decide to stop here and use the framework as is; it's