Merge branch 'bugfix/gpio_example_config_struct_zero_init_v4.2' into 'release/v4.2'

example: fixed the issue that config struct is not properly initialized (v4.2)

See merge request espressif/esp-idf!17589

examples/peripherals/gpio/main/gpio_example_main.c

@@ -59,7 +59,8 @@ static void gpio_task_example(void* arg)
 
 void app_main(void)
 {
-    gpio_config_t io_conf;
+    //zero-initialize the config structure.
+    gpio_config_t io_conf = {};
     //disable interrupt
     io_conf.intr_type = GPIO_PIN_INTR_DISABLE;
     //set as output mode