Add support for rust-coreutils in integration test script.

scripts/run_integration_test.bash

@@ -4,6 +4,8 @@ set -euo pipefail
 IFS=$'\n\t'
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
+REALPATH=$(command -v uu-realpath || command -v realpath)
+
 samples_dir=$(readlink -f "$DIR/../org_mode_samples")
 
 function get_test_names {
@@ -11,7 +13,7 @@ function get_test_names {
     do
         if [ -e "$test_file" ]; then
             test_file_full_path=$(readlink -f "$test_file")
-            relative_to_samples=$(realpath --relative-to "$samples_dir" "$test_file_full_path")
+            relative_to_samples=$($REALPATH --relative-to "$samples_dir" "$test_file_full_path")
             without_extension="${relative_to_samples%.org}"
             echo "${without_extension/\//_}" | tr '[:upper:]' '[:lower:]'
         else