Use sops for private key distribution

nixos/modules/borgbackup.nix

@@ -132,15 +132,6 @@ in {
       };
     };
     environment.persistence.${config.impermanence.name} = {
-      /*
-          users.fsaccount.directories = [
-          {
-            directory = ".ssh"; # SSH Key with access to FS Account and known_hosts
-            mode = "u=rwx,g=,o=";
-          }
-        ];
-      };
-      */
       users.fsaccount.files = [
         {
           file = ".ssh/known_hosts";