Fix an edge case when globbing the working dir

[bglw]

cloudcannon.config.yml

source: .
collections_config:
  docs:
    path: '.'
    glob: '**/*.md'

Currently this will return zero results (thecodrr/fdir#92).

This PR adds a workaround for this one case:

reader/src/generators/collections.js

Lines 15 to 21 in f667b60

	// Work around for https://github.com/thecodrr/fdir/issues/92
	// Globbing on `.` doesn't work, so we crawl using the absolute CWD
	// and get the relative paths of results instead of the base paths.
	if ((crawlDirectory === '.' || crawlDirectory === './') && collectionConfig.glob) {
	crawler = crawler.withRelativePaths();
	crawlDirectory = process.cwd();
	}