update changelog for 4.4.4 release date

Author: madlohe

Changelog

@@ -3,7 +3,7 @@ Nagios Core 4 Change Log
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-4.4.4 - 2019-??-??
+4.4.4 - 2019-07-29
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 * Fixed log rotation logic to not repeatedly schedule rotation on a DST change (#610, #626) (Jaroslav Jindrak & Sebastian Wolf)
 * Fixed $SERVICEPROBLEMID$ to be reset after service recovery (#621) (Sebastian Wolf)