Fix: pgsql fix (#10)

* fix: remove license header from files

* fix: updated docs and sample
---------

Co-authored-by: Marcel S. Henselin <marcel.henselin@stackit.cloud>

sample/postresql.tf

@@ -0,0 +1,36 @@
+resource "stackitprivatepreview_postgresflexalpha_instance" "ptlsdbsrv" {
+  project_id      = var.project_id
+  name            = "pgsql-example-instance"
+  acl             = ["0.0.0.0/0"]
+  backup_schedule = "0 0 * * *"
+  flavor = {
+    cpu = 2
+    ram = 4
+  }
+  replicas = 3
+  storage = {
+    class = "premium-perf2-stackit"
+    size  = 5
+  }
+  encryption = {
+    #    key_id = stackit_kms_key.key.key_id
+    #    keyring_id = stackit_kms_keyring.keyring.keyring_id
+    key_id = var.key_id
+    keyring_id = var.keyring_id
+    key_version = var.key_version
+    service_account = var.sa_email
+  }
+  network = {
+    acl             = ["0.0.0.0/0", "193.148.160.0/19"]
+    access_scope = "SNA"
+  }
+  version = 14
+}
+
+
+resource "stackitprivatepreview_sqlserverflexalpha_user" "ptlsdbuser" {
+  project_id  = stackitprivatepreview_postgresflexalpha_instance.ptlsdbsrv.project_id
+  instance_id = stackitprivatepreview_postgresflexalpha_instance.ptlsdbsrv.id
+  username    = var.db_username
+  roles       = ["createdb", "login", "createrole"]
+}