module tests: add tests for coercedTo

lib/tests/modules/declare-coerced-value.nix

@@ -0,0 +1,10 @@
+{ lib, ... }:
+
+{
+  options = {
+    value = lib.mkOption {
+      default = 42;
+      type = lib.types.coercedTo lib.types.int builtins.toString lib.types.str;
+    };
+  };
+}

lib/tests/modules/define-value-list.nix

@@ -0,0 +1,3 @@
+{
+  value = [];
+}

lib/tests/modules/define-value-string.nix

@@ -0,0 +1,3 @@
+{
+  value = "24";
+}