Env Vars

POST_DRAFT: Include draft posts if set to true. Exclude all other posts if set to only.
POST_NO_GH: Ignore GitHub source if set.
POST_FILTER_FS: A glob pattern to filter posts from file system. Fallback will be "**/*.md".
POST_FILTER_GH: A label to filter posts from GitHub. Fallback will be "+".
POST_SLUG: A RegExp to filter all posts whose slug matches.