ssh-server: Rename sshd_config_stretch to sshd_config

This is to avoid confusion, and stretch is not the new, special one any more.

ssh-server/tasks/main.yml

@@ -10,7 +10,7 @@
 
 - name: ensure sshd is configured
   template:
-    src: sshd_config_stretch.j2
+    src: sshd_config.j2
     dest: /etc/ssh/sshd_config
     owner: root
     group: root