ci: Require PRs in conventional commits syntax (#3937)
ci: Require PRs in conventional commits syntax (#3937)

This will allow automated generation of changelogs and releases based
on PR titles.
tvoli/shaka-player,shaka-project/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,shaka-project/shaka-player,tvoli/shaka-player