Add execution timestamp and echo in A72_alarm_getter.sh

In this commit, an echo statement is added to display the execution timestamp
in the A72_alarm_getter.sh script. The timestamp is printed with the command
'echo 'Ausgeführt um: ''.

Additionally, the script now contains a function called delete_expired_at_jobs
to check and delete expired 'at' jobs. The current time is obtained using the
'date' command and stored in the variable current_time.

A72_alarm_getter.sh

@@ -8,6 +8,8 @@
 # dann das Einschalten der Lichter.
 # mit dem "at" Befehl.
 
+echo "Ausgeführt um: $date"
+
 # Überprüfen, ob alte "at"-Aufträge abgelaufen sind und sie löschen
 delete_expired_at_jobs() {
   current_time=$(date +"%Y-%m-%d %H:%M:%S")