Inconsistent file globbing

[nickmccurdy]

This tool seems to find too many or too few files when globbing. I suspect default includes are the culprit, though I'm not sure if this is just a counting issue or if it affects errors too.

Example from Testing Library

Command	Count
git ls-files "*.md" "*.mdx" | wc -l	115
docusaurus-mdx-checker	111
docusaurus-mdx-checker -c docs	216
docusaurus-mdx-checker -c blog	111

Results appear to be consistent with -c in different directories.