west.yml: Point to hal_stm32 version compatible with STM32WBA BLE

Update west manifest to point to hal_stm32 PR containing changes
which allow to build a zephyr bluetooth application on STM32WBA.

Prior building such application, user should run 'west blobs fetch stm32'
to install binary blobs providing the BLE controller support.

Signed-off-by: Erwan Gouriou <erwan.gouriou@st.com>