telegraf 1.38.2 vendor tarball

telegraf: address review feedback

- Reproducible vendor tarball: honor SOURCE_DATE_EPOCH (clamp-mtime) instead
  of an arbitrary fixed date, matching the grafana/sleef/rust-zip convention.
- Create output folder before resolving the archive path so a clean/nested
  --outFolder works.
- Use brace expansion throughout generate_source_tarball.sh.
- Link the Fedora Go packaging guidelines in telegraf.comp.toml.
- Publish to the base repo by adding telegraf to components-publish-channels.toml.
- Refresh vendor tarball SHA512 (mtime change) in comp.toml + rendered sources.
- Refresh lock.