vars: simplify eval tests by using submodule directly

nixosModules/clanCore/vars/eval-tests/default.nix

@@ -4,7 +4,7 @@ let
     module:
     (lib.evalModules {
       modules = [
-        ../default.nix
+        ../interface.nix
         module
       ];
     }).config;
@@ -13,7 +13,7 @@ in
   single_file_single_prompt =
     let
       config = eval {
-        clan.core.vars.generators.my_secret = {
+        generators.my_secret = {
           files.password = { };
           files.username.secret = false;
           prompts.prompt1 = { };
@@ -25,25 +25,25 @@ in
     in
     {
       test_file_secret_by_default = {
-        expr = config.clan.core.vars.generators.my_secret.files.password.secret;
+        expr = config.generators.my_secret.files.password.secret;
         expected = true;
       };
       test_secret_value_access_raises_error = {
-        expr = config.clan.core.vars.generators.my_secret.files.password.value;
+        expr = config.generators.my_secret.files.password.value;
         expectedError.type = "ThrownError";
         expectedError.msg = "Cannot access value of secret file";
       };
       test_public_value_access = {
-        expr = config.clan.core.vars.generators.my_secret.files.username ? value;
+        expr = config.generators.my_secret.files.username ? value;
         expected = true;
       };
       # both secret and public values must provide a path
       test_secret_has_path = {
-        expr = config.clan.core.vars.generators.my_secret.files.password ? path;
+        expr = config.generators.my_secret.files.password ? path;
         expected = true;
       };
       test_public_var_has_path = {
-        expr = config.clan.core.vars.generators.my_secret.files.username ? path;
+        expr = config.generators.my_secret.files.username ? path;
         expected = true;
       };
     };