Terraform’s VCS providers do not always require webhooks for integration. For example, Bitbucket can allow connections through HTTPS.
Is it possible to connect to a VCS without using webhooks?
At this time, webhooks are required for all VCS integrations. This requirement comes from the Terraform side of the integration. So, although certain VCS providers do not require webhooks they are required from Terraform. Without allowing webhook access, the VCS connection will fail.