[safe_mode] Remove unused capture (#7826)

esphome/components/safe_mode/automation.h

@@ -9,7 +9,7 @@ namespace safe_mode {
 class SafeModeTrigger : public Trigger<> {
  public:
   explicit SafeModeTrigger(SafeModeComponent *parent) {
-    parent->add_on_safe_mode_callback([this, parent]() { trigger(); });
+    parent->add_on_safe_mode_callback([this]() { trigger(); });
   }
 };