fix: postgresqlflex flavor errors (#107)

feat: enable old v2 flavor handling
Co-authored-by: Marcel S. Henselin <marcel.henselin@stackit.cloud>
Reviewed-on: #107

docs/resources/postgresflexalpha_instance.md

@@ -60,11 +60,10 @@ import {
 ### Required
 
 - `backup_schedule` (String) The schedule for when the database backup will be created. Currently, ONLY daily schedules are supported (every 24 hours). The schedule is written as a cron schedule.
-- `flavor_id` (String) The id of the instance flavor.
 - `name` (String) The name of the instance.
 - `network` (Attributes) The access configuration of the instance (see [below for nested schema](#nestedatt--network))
 - `replicas` (Number) How many replicas the instance should have.
-- `retention_days` (Number) How long backups are retained. The value can only be between 32 and 365 days.
+- `retention_days` (Number) How long backups are retained. The value can only be between 32 and 90 days.
 - `storage` (Attributes) The object containing information about the storage size and class. (see [below for nested schema](#nestedatt--storage))
 - `version` (String) The Postgres version used for the instance. See [Versions Endpoint](/documentation/postgres-flex-service/version/v3alpha1#tag/Version) for supported version parameters.
 
@@ -73,6 +72,8 @@ import {
 - `encryption` (Attributes) The configuration for instance's volume and backup storage encryption.
 
 ⚠︝ **Note:** This feature is in private preview. Supplying this object is only permitted for enabled accounts. If your account does not have access, the request will be rejected. (see [below for nested schema](#nestedatt--encryption))
+- `flavor` (Attributes, Deprecated) (see [below for nested schema](#nestedatt--flavor))
+- `flavor_id` (String) The id of the instance flavor.
 - `instance_id` (String) The ID of the instance.
 - `project_id` (String) The STACKIT project ID.
 - `region` (String) The region which should be addressed
@@ -122,6 +123,20 @@ Required:
 - `service_account` (String)
 
 
+<a id="nestedatt--flavor"></a>
+### Nested Schema for `flavor`
+
+Optional:
+
+- `cpu` (Number, Deprecated)
+- `ram` (Number, Deprecated)
+
+Read-Only:
+
+- `description` (String)
+- `id` (String)
+
+
 <a id="nestedatt--connection_info"></a>
 ### Nested Schema for `connection_info`