Returns all webhook subscriptions.

Security: Requires authentication using Access Tokens. You can authenticate using the following methods:

• Administrator Roles: Authenticate as admin, Project Admin, or user with the Platform Admin role.
• User with Manage Webhooks Role: Available from Artifactory version 7.137.0
• Scoped Token: Available from Artifactory version 7.135.0 using the system:webhooks@<project_key>/<JFrog_domain>:r scope.