message: fix: make oclif.s3.folder optional for --indexes
diff: @@ -42,7 +42,8 @@ export const appendToIndex = async (input: { version: string; originalUrl: strin
  // json-friendly filenames like sfdx-linux-x64-tar-gz
  const jsonFileName = `${filename.replace(/\./g, '-')}.json`
  - const key = path.join(s3Config.folder!, 'versions', jsonFileName)
  + // folder is optional, but honored if present
  + const key = path.join(s3Config.folder ?? '', 'versions', jsonFileName)
  // retrieve existing index file
  let existing = {}
  