Remove delay milliseconds test

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>

tests/suites/test_suite_platform.data

@@ -4,6 +4,3 @@ time_get_milliseconds:
 
 Time: get seconds
 time_get_seconds:
-
-Time: delay milliseconds
-time_delay_milliseconds:1000

tests/suites/test_suite_platform.function

@@ -64,6 +64,13 @@ void time_delay_milliseconds(int delay_ms)
     mbedtls_ms_time_t current = mbedtls_ms_time();
     mbedtls_ms_time_t elapsed_ms;
 
+    /*
+     * WARNING: DO NOT ENABLE THIS TEST. We keep the code here to document the
+     *          reason.
+     *
+     *          Windows CI reports random test fail on platform-suite. It might
+     *          be caused by this case.
+     */
     sleep_ms(delay_ms);
 
     elapsed_ms = mbedtls_ms_time() - current;