feat(iaas): min/max acc tests (#811)

* feat(iaas): security group min/max acc test

* feat(iaas): image min/max acc test

* feat(iaas): KeyPair min/max acc test

* feat(iaas): Network area min/max acc test
- fix: wrong atLeast-validator for `minimum_prefix_length`

* feat(iaas): Network min/max acc test

* feat(iaas): Volume min/max acc test
- fix: volume update doesn't work if no name was defined
- fix: volume.server_id can not be set
- fix: error message volume.size returns value but was null

* feat(iaas): Network interfaces min/max acc test

* feat(iaas): Affinity groups acc test

* feat(iaas): Server min/max acc test
- stackit_server_volume_attach
- stackit_server_network_interface_attach
- stackit_server_service_account_attach

* fix(iaas): acc test
- image: fix read of Config.VirtioScsi
- keypair: add missing RequiresReplace() for name
- server: add missing UserData read in datasource and resource

* feat(iaas): public ip acc test
- fix: when a nic is assigned to a public ip, the field network_interface_id leads to recreation

stackit/internal/services/iaas/testdata/resource-volume-max.tf

@@ -0,0 +1,35 @@
+variable "project_id" {}
+variable "availability_zone" {}
+variable "name" {}
+variable "size" {}
+variable "description" {}
+variable "performance_class" {}
+variable "label" {}
+
+resource "stackit_volume" "volume_size" {
+  project_id        = var.project_id
+  availability_zone = var.availability_zone
+  name              = var.name
+  size              = var.size
+  description       = var.description
+  performance_class = var.performance_class
+  labels = {
+    "acc-test" : var.label
+  }
+}
+
+resource "stackit_volume" "volume_source" {
+  project_id        = var.project_id
+  availability_zone = var.availability_zone
+  name              = var.name
+  description       = var.description
+  performance_class = var.performance_class
+  size = var.size
+  source = {
+    id   = stackit_volume.volume_size.volume_id
+    type = "volume"
+  }
+  labels = {
+    "acc-test" : var.label
+  }
+}