chore(release): 1.0.0-alpha.60 [skip ci]

# [1.0.0-alpha.60](https://code.podlibre.org/podlibre/castopod-host/compare/v1.0.0-alpha.59...v1.0.0-alpha.60) (2021-06-21)

### Features

* **rss:** add ˂podcast:guid˃ tag for channel ([1fab10eb](https://code.podlibre.org/podlibre/castopod-host/commit/1fab10eb0d63bb7c3edf34ffe691e2aec2c2e43c))