(DOCSP-46441) Typo fix. (#548)

Author: elyse-mdb

source/reference/configuration.txt

@@ -13,7 +13,7 @@ Configuration
    :class: singlecol
 
 You can configure :ref:`mongosync <c2c-mongosync>` instances at startup 
-by using :reF:`command line options <c2c-cli-options>` or a configuration file.
+by using :ref:`command line options <c2c-cli-options>` or a configuration file.
 The configuration file specifies values for settings that are
 the equivalent of ``mongosync`` command line options.