test: fix gradient test by using more specific querySelector (#1954)

Author: qimolin

tests/card.test.js

@@ -168,18 +168,18 @@ describe("Card", () => {
       "fill",
       "url(#gradient)",
     );
-    expect(document.querySelector("defs linearGradient")).toHaveAttribute(
+    expect(document.querySelector("defs #gradient")).toHaveAttribute(
       "gradientTransform",
       "rotate(90)",
     );
     expect(
-      document.querySelector("defs linearGradient stop:nth-child(1)"),
+      document.querySelector("defs #gradient stop:nth-child(1)"),
     ).toHaveAttribute("stop-color", "#fff");
     expect(
-      document.querySelector("defs linearGradient stop:nth-child(2)"),
+      document.querySelector("defs #gradient stop:nth-child(2)"),
     ).toHaveAttribute("stop-color", "#000");
     expect(
-      document.querySelector("defs linearGradient stop:nth-child(3)"),
+      document.querySelector("defs #gradient stop:nth-child(3)"),
     ).toHaveAttribute("stop-color", "#f00");
   });
 });