samples: net: wpan_serial: Excluding nucleo_wba65ri platform As CONFIG_BUILD_ONLY_NO_BLOBS feature is not implemented for stm32wbax socs, we have temporarily excluded nucleo_wba65ri platform from CI build tests. Issue https://github.com/zephyrproject-rtos/zephyr/issues/95495 will be updated accordingly Signed-off-by: Alessandro Manganaro <alessandro.manganaro@st.com>