Fix ignore_file option in S3Bucket

[neumann-nico]

Closes #140

Example

When using S3Bucket.put_directory(ignore_file=".prefectignore") the filter_files function is called which returns the included_files as strings. But the actual files are of type path.PosixPath and includes the whole absolute path.
As an example:

# .prefectignore
**/folder2/*

# called with S3Bucket.put_directory(local_path=str(tmp_path / "folder1"), ignore_file=".prefectignore"))
included_files = {'file3.txt', 'folder2', 'file4.txt'}
# not sure why the directory folder2 is included here, but the files inside folder 2 are excluded. The upload function skips directories, so thats not a big problem.
# looping over the files using local_file_path
pathlib.PosixPath("/private/var/folders/h0/jxdxc2_93m74hnycmnckqb3w0000gn/T/pytest-of-niconeumann/pytest-21/test_put_directory_with_ignore1/folder1/file3.txt")
pathlib.PosixPath("/private/var/folders/h0/jxdxc2_93m74hnycmnckqb3w0000gn/T/pytest-of-niconeumann/pytest-21/test_put_directory_with_ignore1/folder1/file4.txt")
pathlib.PosixPath("/private/var/folders/h0/jxdxc2_93m74hnycmnckqb3w0000gn/T/pytest-of-niconeumann/pytest-21/test_put_directory_with_ignore1/folder1/folder2")
pathlib.PosixPath("/private/var/folders/h0/jxdxc2_93m74hnycmnckqb3w0000gn/T/pytest-of-niconeumann/pytest-21/test_put_directory_with_ignore1/folder1/folder2/file5.txt")

It tries to find those absolute posix paths in the included files, which does not work and thus skips files which should be uploaded:

if included_files is not None and local_path not in included_files:
    continue

Instead I use the relative path and parse it to a string:

if (
    included_files is not None
    and str(local_file_path.relative_to(local_path)) not in included_files
):
    continue

# called with S3Bucket.put_directory(local_path=str(tmp_path / "folder1"), ignore_file=".prefectignore"))
included_files = {'file3.txt', 'folder2', 'file4.txt'}
# looping over the files using str(local_file_path.relative_to(local_path)
"file3.txt"
"file4.txt"
"folder2"
"folder2/file5.txt"

Checklist

• This pull request references any related issue by including "Closes #<ISSUE_NUMBER>"
  • If no issue exists and your change is not a small fix, please create an issue first.
• This pull request includes tests or only affects documentation.
• Summarized PR's changes in CHANGELOG.md

[desertaxle]

Thanks for identifying and contributing a fix so quickly!