try caching downloaded file

.github/workflows/run_integration_tests.yml

@@ -16,5 +16,16 @@ jobs:
         with:
           dotnet-version: "2.1.x"
 
+      - name: Restore cached part 2
+        id: restore-cache-p2
+        uses: actions/cache@v2
+        with:
+          path: archive/part2-archive.7z
+          key: ${{ runner.os }}-part-2
+
       - name: Download the archive
-        run: mkdir archive && wget http://eliot-jones.com:8081/part2-archive.7z -P archive/ && ls archive
+        if: steps.restore-cache-p2.outputs.cache-hit != 'true'
+        run: mkdir archive && wget http://eliot-jones.com:8081/part2-archive.7z -nv -P archive/ && ls archive
+
+      - name: Print output size
+        run: stat --printf="%s" archive/part2-archive.7z