Build command:
"cmake -G"Unix Makefiles" -S . -B build -DTFM_PLATFORM=mps2/an521 -DTFM_TOOLCHAIN_FILE=toolchain_GNUARM.cmake -DTEST_NS=ON -DTEST_S=OFF -DTFM_PSA_API=ON -DTFM_ISOLATION_LEVEL=3 ../"

There would be a test error. It was caused by TFM_SP_SECURE_CLIENT_2 is missing, but the non-secure client is still there. Connecting to an unknown SID would cause a panic