uart: drivers: uart: uart_elementary: update testcase.yaml

- Remove nucleo_h743zi from CI testing since it is not
supported by this test.

Signed-off-by: Fabrice DJIATSA <[email protected]>

Author: djiatsaf-st

tests/drivers/uart/uart_elementary/testcase.yaml

@@ -32,7 +32,7 @@ tests:
       - nucleo_f091rc
       - nucleo_g071rb
       - nucleo_g474re
-      - nucleo_h743zi
+      - nucleo_h753zi
       - nucleo_l152re
       - stm32n6570_dk/stm32n657xx/sb
       - stm32u083c_dk