Change orchagent stuck message from ERR to WARNING (#17872)

Change orchagent stuck message from ERR to WARNING

#### Why I did it
During switch initialization, sometime Orchagent will busy for more than 40seconds and will trigger process stuck workdog error.
To improve this issue, change watchdog error message to warning message.

##### Work item tracking
- Microsoft ADO: 26517622

#### How I did it
Change orchagent stuck message from ERR to WARNING.

#### How to verify it
Pass all UT.

### Description for the changelog
Change orchagent stuck message from ERR to WARNING.

files/scripts/supervisor-proc-exit-listener

@@ -73,7 +73,7 @@ def get_group_and_process_list(process_file):
     return group_list, process_list
 
 
-def generate_alerting_message(process_name, status, dead_minutes):
+def generate_alerting_message(process_name, status, dead_minutes, priority=syslog.LOG_ERR):
     """
     @summary: If a critical process was not running, this function will determine it resides in host
               or in a specific namespace. Then an alerting message will be written into syslog.
@@ -86,7 +86,7 @@ def generate_alerting_message(process_name, status, dead_minutes):
     else:
         namespace = namespace_prefix + namespace_id
 
-    syslog.syslog(syslog.LOG_ERR, "Process '{}' is {} in namespace '{}' ({} minutes)."
+    syslog.syslog(priority, "Process '{}' is {} in namespace '{}' ({} minutes)."
                   .format(process_name, status, namespace, dead_minutes))
 
 
@@ -213,7 +213,7 @@ def main(argv):
             elapsed_secs = epoch_time - process_heart_beat_info[process]["last_heart_beat"]
             if elapsed_secs >= ALERTING_INTERVAL_SECS:
                 elapsed_mins = elapsed_secs // 60
-                generate_alerting_message(process, "stuck", elapsed_mins)
+                generate_alerting_message(process, "stuck", elapsed_mins, syslog.LOG_WARNING)
 
 if __name__ == "__main__":
     main(sys.argv[1:])