protocol_examples_common: keep buffering enabled on stdout

- Newlib uses significantly more stack space when printing to an unbuffered stream
- For examples tests, disabling buffering on stdout is not really required

This issue was found during one of the OTA example test failure, root cause
being stack overflow in `esp_event` task.

examples/common_components/protocol_examples_common/stdin_out.c

@@ -17,7 +17,6 @@ esp_err_t example_configure_stdin_stdout(void)
 {
     // Initialize VFS & UART so we can use std::cout/cin
     setvbuf(stdin, NULL, _IONBF, 0);
-    setvbuf(stdout, NULL, _IONBF, 0);
     /* Install UART driver for interrupt-driven reads and writes */
     ESP_ERROR_CHECK( uart_driver_install( (uart_port_t)CONFIG_ESP_CONSOLE_UART_NUM,
             256, 0, 0, NULL, 0) );