Incompatible slugs for digitalocean_uptime_alert

[MauriceArikoglu]

Terraform suggests valid slug values for the period property of an uptime alert as follows:

Error: expected period to be one of [2m 3m 5m 10m 15m 30m 1hr], got 1h

Switching to 1hr causes the terraform apply to fail with this error:

Error: Error creating Uptime Alert: POST https://api.digitalocean.com/v2/uptime/checks/$id/alerts: 400 (request "request_id") invalid value for field 'period': unsupported period value '1hr'

According to the documentation the correct value is 1h