minor #20207 [AssetMapper] Add missing backticks for inline snippets (phansys)

This PR was merged into the 6.4 branch.

Discussion
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[AssetMapper] Add missing backticks for inline snippets

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Commits
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a79a579 [AssetMapper] Add missing backticks for inline snippets

Author: javiereguiluz

frontend/asset_mapper.rst

@@ -967,7 +967,7 @@ This option is enabled by default.
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Configure the polyfill for older browsers. By default, the `ES module shim`_ is loaded
-via a CDN (i.e. the default value for this setting is `es-module-shims`):
+via a CDN (i.e. the default value for this setting is ``es-module-shims``):
 
 .. code-block:: yaml