Update interface-definitions/system_flow-accounting.xml.in

Co-authored-by: Daniil Baturin <daniil@baturin.org>

Author: hedrok

interface-definitions/system_flow-accounting.xml.in

@@ -120,7 +120,7 @@
                   <help>Flow inactivity timeout</help>
                   <valueHelp>
                     <format>u32:0-2147483647</format>
-                    <description>Timeout to export inactive flow, seconds</description>
+                    <description>Inactive flow export timeout (seconds)</description>
                   </valueHelp>
                   <constraint>
                     <validator name="numeric" argument="--range 0-2147483647"/>