Remove old xeon07 hostname in raccoon and tent ssh config

xeon07 has been renamed to hut in apex /etc/hosts

m/module/ssh-hut-extern.nix

@@ -1,9 +1,8 @@
 {
   programs.ssh.extraConfig = ''
-    Host ssfhead
+    Host apex ssfhead
       HostName ssflogin.bsc.es
     Host hut
-      ProxyJump ssfhead
+      ProxyJump apex
-      HostName xeon07
   '';
 }