[slow_pwm] Fix dump_summary deprecation warning

esphome/components/slow_pwm/slow_pwm_output.cpp

@@ -1,6 +1,7 @@
 #include "slow_pwm_output.h"
-#include "esphome/core/log.h"
 #include "esphome/core/application.h"
+#include "esphome/core/gpio.h"
+#include "esphome/core/log.h"
 
 namespace esphome {
 namespace slow_pwm {
@@ -20,7 +21,9 @@ void SlowPWMOutput::set_output_state_(bool new_state) {
   }
   if (new_state != current_state_) {
     if (this->pin_) {
-      ESP_LOGV(TAG, "Switching output pin %s to %s", this->pin_->dump_summary().c_str(), ONOFF(new_state));
+      char pin_summary[GPIO_SUMMARY_MAX_LEN];
+      this->pin_->dump_summary(pin_summary, sizeof(pin_summary));
+      ESP_LOGV(TAG, "Switching output pin %s to %s", pin_summary, ONOFF(new_state));
     } else {
       ESP_LOGV(TAG, "Switching to %s", ONOFF(new_state));
     }