Close gzip reader as per documentation (#187)

Author: bhavikkumar

events/cloudwatch_logs.go

@@ -26,6 +26,7 @@ func (c CloudwatchLogsRawData) Parse() (d CloudwatchLogsData, err error) {
 	}
 
 	zr, err := gzip.NewReader(bytes.NewBuffer(data))
+	defer zr.Close()
 	if err != nil {
 		return
 	}