minor #2027 [Doc] Fix some misc issues in UX Icons docs (javiereguiluz)

This PR was merged into the 2.x branch.

Discussion
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[Doc] Fix some misc issues in UX Icons docs

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Issues        | -
| License       | MIT

This fixes the doc issues reported in https://symfony.com/doc/build_errors#ux-icons-2.x

The relative URL links don't work because the UX docs are considered a different book from Symfony Docs, so relative links like `:doc: ... </templates>` can't be resolved.

Commits
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c476e3a [Doc] Fix some misc issues in UX Icons docs

Author: javiereguiluz

src/Icons/doc/index.rst

@@ -384,11 +384,10 @@ of the following attributes: ``aria-label``, ``aria-labelledby`` or ``title``.
     If you don't want to set ``aria-hidden="true"`` for a specific icon, you can
     explicitly set the ``aria-hidden`` attribute to ``false``:
 
-    .. code-block:: twig+html
+    .. code-block:: html+twig
 
         <twig:ux:icon name="user-profile" aria-hidden="false" />
 
-
 Performance
 -----------
 
@@ -458,7 +457,7 @@ returning the HTML output.
 
     The <twig:ux:icon> component does not support embedded content.
 
-    .. code-block:: twig+html
+    .. code-block:: html+twig
 
         {# The 🧸 will be ignore in the HTML output #}
         <twig:ux:icon name="user-profile" class="w-4 h-4">🧸</twig:ux:icon>
@@ -519,8 +518,8 @@ Full Configuration
 Learn more
 ----------
 
-* :doc:`Creating and Using Templates </templates>`
-* :doc:`How to manage CSS and JavaScript assets in Symfony applications </frontend>`
+* `Creating and Using Templates`_
+* `How to manage CSS and JavaScript assets in Symfony applications`_
 
 .. _`SVG`: https://en.wikipedia.org/wiki/SVG
 .. _`ux.symfony.com/icons`: https://ux.symfony.com/icons
@@ -539,3 +538,5 @@ Learn more
 .. _`Octicons`: https://github.com/primer/octicons/
 .. _`Phosphor Icons`: https://github.com/phosphor-icons/homepage
 .. _`Tabler Icons`: https://github.com/tabler/tabler-icons
+.. _`Creating and Using Templates`: https://symfony.com/doc/current/templates.html
+.. _`How to manage CSS and JavaScript assets in Symfony applications`: https://symfony.com/doc/current/frontend.html