Fix double yaml file extention in manifests_path

[powellchristoph]

When using the manifests_path feature, it adds an extra .yaml file extension to the rendered files.

The fileset globs for the yaml extension and includes it in the base64gzip. The template doubles it.
https://github.com/remche/terraform-openstack-rke2/blob/master/modules/node/main.tf#L37

Files in the module.

~/Repos/datto/tf_rancher/modules/rke2 main* ❯ grep manifests main.tf
  manifests_path  = "${path.module}/manifests"

~/Repos/datto/tf_rancher/modules/rke2 main* ❯ ll manifests
total 128
-rw-r--r--  1 cpowell  staff   477B Jul 27  2022 snapshot-class.yaml
-rw-r--r--  1 cpowell  staff   2.6K Jun 20  2022 snapshot-controller.yaml
-rw-r--r--  1 cpowell  staff    53K Jun 20  2022 snapshotter-crds.yaml

Renders the following on disk.

root@test-server-001:/var/lib/rancher/rke2/server/manifests# ll
total 364
drwxr-xr-x 2 root root   4096 Jun 12 15:40 ./
drwxr-xr-x 8 root root   4096 Jun 10 15:32 ../
-rw-r--r-- 1 root root 185919 Jun 12 15:39 rke2-calico-crd.yaml
-rw-r--r-- 1 root root  17779 Jun 12 15:39 rke2-calico.yaml
-rw-r--r-- 1 root root  27797 Jun 12 15:39 rke2-coredns.yaml
-rw------- 1 root root    477 Jun  6 16:52 snapshot-class.yaml.yaml
-rw------- 1 root root   2676 Jun  6 16:52 snapshot-controller.yaml.yaml
-rw------- 1 root root  54735 Jun  6 16:52 snapshotter-crds.yaml.yaml

[remche]

It's a behavior I had observed but never took the time to correct... Thank you!