nixos/tests/ec2: rename ec2-nixops to ec2-userdata

This is more accurate.

People dismissed failures in the past in this test because of the name.
We don't want that. The test is important! It tests that SSH works!

Hopefully this helps with https://github.com/NixOS/nixpkgs/pull/340489#issuecomment-2531494744

nixos/tests/all-tests.nix

@@ -490,7 +490,7 @@ in
   earlyoom = runTestOn [ "x86_64-linux" ] ./earlyoom.nix;
   easytier = runTest ./easytier.nix;
   ec2-image = runTest ./ec2-image.nix;
-  ec2-nixops = (handleTestOn [ "x86_64-linux" ] ./ec2.nix { }).ec2-nixops or { };
+  ec2-userdata = (handleTestOn [ "x86_64-linux" ] ./ec2.nix { }).ec2-userdata or { };
   echoip = runTest ./echoip.nix;
   ejabberd = runTest ./xmpp/ejabberd.nix;
   elk = handleTestOn [ "x86_64-linux" ] ./elk.nix { };

nixos/tests/ec2.nix

@@ -44,8 +44,8 @@ let
 
 in
 {
-  ec2-nixops = makeEc2Test {
-    name = "nixops-userdata";
+  ec2-userdata = makeEc2Test {
+    name = "ec2-userdata";
     meta.timeout = 600;
     inherit image;
     sshPublicKey = snakeOilPublicKey; # That's right folks! My user's key is also the host key!