Add ability to upload assets after release has been created

[inlife]

Hello

Would be nice to have an ability to provide tools for uploading assets (compiled binaries, custom archives, and other types of artifacts). The easiest possible way I see would be probably by modifying the hooks to support additional functions.

module.exports = async (markdown, metaData) => {
  // Use the available data to create a custom release
  return markdown
}

/**
 * @param github - an authorized @octokit/rest instance
 * @param uploadUrl - part of http response for create release request
 */
module.exports.post = async (github, uploadUrl) => {
  github.repos.uploadReleaseAsset({
    uploadUrl, headers, name, file
  })
}