Reduce number of calls to fetch time in the main loop (#8804)

esphome/components/time_based/time_based_cover.cpp

@@ -1,6 +1,7 @@
 #include "time_based_cover.h"
 #include "esphome/core/log.h"
 #include "esphome/core/hal.h"
+#include "esphome/core/application.h"
 
 namespace esphome {
 namespace time_based {
@@ -26,7 +27,7 @@ void TimeBasedCover::loop() {
   if (this->current_operation == COVER_OPERATION_IDLE)
     return;
 
-  const uint32_t now = millis();
+  const uint32_t now = App.get_loop_component_start_time();
 
   // Recompute position every loop cycle
   this->recompute_position_();