Fixed a mistake i made in the example restart script

Playwright-content-fetcher.md

@@ -147,7 +147,7 @@ Create a file named `restart-changedetection.sh` with your favorite text editor,
 ps -C changedetection u|grep -v PID|awk '$6 > 240000 {print $2};'|while read pid
 do
   kill -9 $pid
-  systemctl start changedetection.service
+  systemctl restart changedetection.service
 done
 ```