man: Fix spelling error

Regression introduced in commit 30d45ed5ccc3b9cf1f7cc745a1f293137ec958aa.

Warned-by: lintian

man/update-alternatives.1

@@ -354,7 +354,7 @@ Specifies the log file (since version 1.15.0), when this is to be different
 from the default (/var/log/alternatives.log).
 .TP
 .BI \-\-force
-Allows to replace or drop any real file that is installed
+Allow replacing or dropping any real file that is installed
 where an alternative link has to be installed or removed.
 .TP
 .BI \-\-skip\-auto