[RAM] Remove restriction on setting a start time in the past on Snooz…

…e Scheduler UI (#168160)

## Summary

Closes #167176

Sets the minimum date in the snooze scheduler datepicker to the current
date at `00:00`. This is useful especially when the user is trying to
create a recurring schedule that starts today, and should start at a
time earlier than the current time on future occurrences.

x-pack/plugins/triggers_actions_ui/public/application/sections/rules_list/components/rule_snooze/scheduler.tsx

@@ -121,7 +121,15 @@ const RuleSnoozeSchedulerPanel: React.FunctionComponent<PanelOpts> = ({
   const minDate = useMemo(
     // If the initial schedule is earlier than now, set minDate to it
     // Set minDate to now if the initial schedule is in the future
-    () => moment.min(moment(), moment(initialSchedule?.rRule.dtstart ?? undefined)),
+    () =>
+      moment
+        .min(moment(), moment(initialSchedule?.rRule.dtstart ?? undefined))
+        // Allow the time on minDate to be earlier than the current time
+        // This is useful especially when the user is trying to create a recurring schedule
+        // that starts today, and should start at a time earlier than the current time on future
+        // occurrences
+        .hour(0)
+        .minute(0),
     [initialSchedule]
   );