Add a per plugin option to reduce cadence of releases

[mfridman]

Something equivalent to Depednabot's schedule.interval. Some plugins are very noisy (e.g., community/stephenh-ts-proto) and we'd like to tune how often they get released.

We noticed some plugins get updated frequently upstream, but do not change the underlying generator.

[rustatian]

Hey @mfridman 👋
roadrunner-server-php-grpc plugin was updated to version 5. It would be nice to trigger an update for it [v5.0.2].

[mfridman]

Thanks for flagging it, I'll review version 5 and if it passes all the tests push it through.

I'll also quickly hammer this issue out so we don't have to manually keep track of certain plugins and instead rely on a lowered cadence.

[mfridman]

Opened #1345 to add the v5