Set LIBRARY_PATH as safer method to use stubs

Author: robballantyne

.github/workflows/build-cuda.yml

@@ -142,9 +142,9 @@ jobs:
               cd llama.cpp
               
               echo '=== Configuring build with Ninja ==='
+              export LIBRARY_PATH="/usr/local/cuda/lib64/stubs${LIBRARY_PATH:+:$LIBRARY_PATH}"
               cmake -B build -S . \
                 -G Ninja \
-                -DCMAKE_EXE_LINKER_FLAGS="-L/usr/local/cuda/lib64/stubs" \
                 -DGGML_CUDA=ON \
                 -DCMAKE_CUDA_ARCHITECTURES='${{ matrix.architectures }}' \
                 -DCMAKE_BUILD_TYPE=Release \