[clang-tidy] Concatenate nested namespaces (4/7: components n-r) (#16301)

esphome/components/pulse_width/pulse_width.cpp

@@ -1,8 +1,7 @@
 #include "pulse_width.h"
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace pulse_width {
+namespace esphome::pulse_width {
 
 static const char *const TAG = "pulse_width";
 
@@ -27,5 +26,4 @@ void PulseWidthSensor::update() {
   this->publish_state(width);
 }
 
-}  // namespace pulse_width
-}  // namespace esphome
+}  // namespace esphome::pulse_width