minor #17601 fix: typo (norival)

This PR was merged into the 5.4 branch.

Discussion
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fix: typo

Commits
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198418d fix: typo

Author: javiereguiluz

reference/configuration/security.rst

@@ -912,7 +912,7 @@ Learn more about user checkers in :doc:`/security/user_checkers`.
 providers
 ---------
 
-This options defines how the application users are loaded (from a database,
+This option defines how the application users are loaded (from a database,
 an LDAP server, a configuration file, etc.) Read
 :doc:`/security/user_providers` to learn more about each of those
 providers.