Try to add a workaround for archiving sample output in parent dir

- The upload-artifact action supposedly supports relative paths, but
  it threw an error when relative paths were used. There also seems to
  be a few open bugs reported on GitHub, here's one: actions/upload-artifact#176.

- Since some of the samples dump their output in the parent directory, let's
  try a workaround to see if we can archive them in the workflow run.

.github/workflows/test-dotnet-samples.yml

@@ -165,6 +165,11 @@ jobs:
               run: |
                 sample_name=$(basename "$PWD")
                 echo "SAMPLE_NAME=$sample_name" >> "$GITHUB_ENV"
+                echo "Set $sample_name as SAMPLE_NAME environment variable"
+
+                sample_parent_dir_path=$(realpath ..)
+                echo "SAMPLE_PARENT_DIR_PATH=$sample_parent_dir_path" >> "$GITHUB_ENV"
+                echo "Set $sample_parent_dir_path as SAMPLE_PARENT_DIR_PATH environment variable"
             - name: Save artifacts
               uses: actions/upload-artifact@v4
               with:
@@ -183,7 +188,7 @@ jobs:
                   ${{matrix.dir}}*.gif
                   ${{matrix.dir}}*.json
                   ${{matrix.dir}}*.txt
-                  ${{matrix.dir}}../*.pdf
-                  ${{matrix.dir}}../*.json
-                  ${{matrix.dir}}../*.txt
-                  ${{matrix.dir}}../*.csv
+                  ${{env.SAMPLE_PARENT_DIR_PATH}}*.pdf
+                  ${{env.SAMPLE_PARENT_DIR_PATH}}*.json
+                  ${{env.SAMPLE_PARENT_DIR_PATH}}*.txt
+                  ${{env.SAMPLE_PARENT_DIR_PATH}}*.csv