formats.pdf.buttons.download.href produces one too many ../

[nbanyan]

As identified in the conversation for issue #59, formats.pdf.buttons.download.href results in one too many parent directory references.

mkdocs-exporter/mkdocs_exporter/formats/pdf/buttons/download.py

Line 15 in 0d4eae0

return os.path.relpath(page.formats['pdf']['url'], page.url)

os.path.relpath assumes the source argument is a directory, so when it receives a file path the file's name is also treated like a directory.

This would be resolved with the following:

return os.path.relpath(page.formats['pdf']['url'], os.path.dirname(page.url))

[niclasheinz]

This behaviour only occurs when the ‘offline’ plugin is activated.

[nbanyan]

When I investigated and tested this with my project, I found identical behavior with this href generation regardless of whether offline was enabled.
Seems like this is the same issue reported in #44. However use_directory_urls doesn't change this behavior for me either.