docs: add empty lines

Author: kenjis

user_guide_src/source/concepts/structure.rst

@@ -75,6 +75,7 @@ public
 
 The **public** folder holds the browser-accessible portion of your web application,
 preventing direct access to your source code.
+
 It contains the main **.htaccess** file, **index.php**, and any application
 assets that you add, like CSS, javascript, or images.
 
@@ -97,8 +98,9 @@ tests
 
 This directory is set up to hold your test files. The **_support** directory
 holds various mock classes and other utilities that you can use while writing
-your tests. This directory does not need to be transferred to your production
-servers.
+your tests.
+
+This directory does not need to be transferred to your production servers.
 
 Modifying Directory Locations
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