Low expires for JWT token. Why? Configurable?

[WilliamDEdwards]

Since upgrading to Sensu 6.12, scripts running sensuctl are failing with:

 Error: API error: failed to request new refresh token; client returned 'The server returned the error: 401 Request unauthorized'

Looking at .config/sensu/sensuctl/cluster (where sensuctl stores tokens), I discovered that expires_at is set 5 minutes.

First of all: was the validity period changed? I can't tell, as this version has no documentation nor release notes: sensu/sensu-docs#4215. We've not experienced any issues before Sensu 6.12, though.

Second of all: is the validity period changeable? It's overly short, and therefore impractical. We don't call sensuctl every 5 minutes, nor do we want to. https://docs.sensu.io/sensu-go/latest/observability-pipeline/observe-schedule/backend/#backend-configuration-options doesn't show a configuration option.