Replace K64F with NUCLEO_F411RE in the test runner example

Author: janjongboom

docs/tools/testing/testing_greentea.md

@@ -139,22 +139,22 @@ Let's run this test (tip: to see all tests, run `mbed test --compile-list`):
 $ mbed test -t GCC_ARM -m auto -v -n tests-test-group-simple-test
 ```
 
-This will yield (on a K64F):
+This will yield (on a NUCLEO F411RE):
 
 ```
 mbedgt: test suite report:
-+--------------+---------------+------------------------------+--------+--------------------+-------------+
-| target       | platform_name | test suite                   | result | elapsed_time (sec) | copy_method |
-+--------------+---------------+------------------------------+--------+--------------------+-------------+
-| K64F-GCC_ARM | K64F          | tests-test-group-simple-test | OK     | 16.84              | default     |
-+--------------+---------------+------------------------------+--------+--------------------+-------------+
++-----------------------+---------------+------------------------------+--------+--------------------+-------------+
+| target                | platform_name | test suite                   | result | elapsed_time (sec) | copy_method |
++-----------------------+---------------+------------------------------+--------+--------------------+-------------+
+| NUCLEO_F411RE-GCC_ARM | NUCLEO_F411RE | tests-test-group-simple-test | OK     | 16.84              | default     |
++-----------------------+---------------+------------------------------+--------+--------------------+-------------+
 mbedgt: test suite results: 1 OK
 mbedgt: test case report:
-+--------------+---------------+------------------------------+-------------+--------+--------+--------+--------------------+
-| target       | platform_name | test suite                   | test case   | passed | failed | result | elapsed_time (sec) |
-+--------------+---------------+------------------------------+-------------+--------+--------+--------+--------------------+
-| K64F-GCC_ARM | K64F          | tests-test-group-simple-test | simple test | 1      | 0      | OK     | 0.01               |
-+--------------+---------------+------------------------------+-------------+--------+--------+--------+--------------------+
++-----------------------+---------------+------------------------------+-------------+--------+--------+--------+--------------------+
+| target                | platform_name | test suite                   | test case   | passed | failed | result | elapsed_time (sec) |
++-----------------------+---------------+------------------------------+-------------+--------+--------+--------+--------------------+
+| NUCLEO_F411RE-GCC_ARM | NUCLEO_F411RE | tests-test-group-simple-test | simple test | 1      | 0      | OK     | 0.01               |
++-----------------------+---------------+------------------------------+-------------+--------+--------+--------+--------------------+
 mbedgt: test case results: 1 OK
 mbedgt: completed in 18.64 sec
 ```