Revert LD_LIBRARY_PATH hack

Author: WillAyd

ci/scripts/cpp_build.sh

@@ -140,9 +140,6 @@ if [ "${ARROW_USE_MESON:-OFF}" = "ON" ]; then
       fi
     fi
   fi
-
-  export CUDA_PATH="${CONDA_PREFIX}"
-  env
   meson setup \
     --prefix=${MESON_PREFIX:-${ARROW_HOME}} \
     --buildtype=${ARROW_BUILD_TYPE:-debug} \

ci/scripts/cpp_test.sh

@@ -31,7 +31,7 @@ binary_output_dir=${build_dir}/${ARROW_BUILD_TYPE:-debug}
 
 export ARROW_TEST_DATA=${arrow_dir}/testing/data
 export PARQUET_TEST_DATA=${source_dir}/submodules/parquet-testing/data
-export LD_LIBRARY_PATH=${ARROW_HOME}/${CMAKE_INSTALL_LIBDIR:-lib}:${CUDA_PATH}/lib/stubs:${LD_LIBRARY_PATH}
+export LD_LIBRARY_PATH=${ARROW_HOME}/${CMAKE_INSTALL_LIBDIR:-lib}:${LD_LIBRARY_PATH}
 
 # By default, aws-sdk tries to contact a non-existing local ip host
 # to retrieve metadata. Disable this so that S3FileSystem tests run faster.