Scheduler with type "Immediate", click Execute does not run the command

Fixes #3092

src/web/WebSchedulerService.h

@@ -88,6 +88,8 @@ class WebSchedulerService : public StatefulService<WebScheduler> {
     uint8_t count_entities(bool cmd_only = false);
     bool    onChange(const char * cmd);
 
+    bool executeSchedule(const char * name);
+
     std::string get_metrics_prometheus();
 
     std::string raw_value;