docs: fix wrong paths in sample commands

Author: kenjis

user_guide_src/source/libraries/sessions.rst

@@ -504,9 +504,9 @@ permissions will probably break your application.
 Instead, you should do something like this, depending on your environment
 ::
 
-    mkdir /<path to your application directory>/Writable/sessions/
-    chmod 0700 /<path to your application directory>/Writable/sessions/
-    chown www-data /<path to your application directory>/Writable/sessions/
+    mkdir /<path to your application directory>/writable/sessions/
+    chmod 0700 /<path to your application directory>/writable/sessions/
+    chown www-data /<path to your application directory>/writable/sessions/
 
 Bonus Tip
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