minor #732 Minor - Adding session dependency caution message (jmontoyaa)

This PR was merged into the master branch.

Discussion
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Minor - Adding session dependency caution message

Commits
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4eab2bd3 Update security.rst
c0a54314 Minor - Adding session dependency caution message

doc/providers/security.rst

@@ -71,6 +71,10 @@ Registering
     don't forget to call ``boot()`` first::
 
         $application->boot();
+        
+.. caution::
+
+    If you're using a form to authenticate users the security provider requires the SessionServiceProvider.
 
 Usage
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