chore(tests): update S3 compat tests

While present, the S3 compatibility tests were broken (at the very
least when running on Linux) due to a few issues:

- `ubuntu:latest` moving ahead of Python 3.6
- Docker networking not working as expected (host.docker.internal)

This commit fixes the s3 compatibility tests, ensuring they run
properly on linux, and updates the repository to contain some results.

Signed-off-by: vados <vados@vadosware.io>

test/s3/compatibility/.gitignore

@@ -1,2 +1,8 @@
+# Test run scratch data
 /s3-tests
 /tmp
+
+# Test run outputs
+weed.log
+compat.raw.txt
+compat.summary.txt