pre-commit: apply autofixes hooks and fix the rest manually

- markdownlint (manual fix)
- end-of-file-fixer
- requirements-txt-fixer
- trailing-whitespace

contrib/terraform/upcloud/modules/kubernetes-cluster/main.tf

@@ -558,4 +558,4 @@ resource "upcloud_server_group" "server_groups" {
   anti_affinity_policy = each.value.anti_affinity_policy
   labels               = {}
   members              = [for server in each.value.servers : merge(upcloud_server.master, upcloud_server.worker)[server].id]
-}
+}