Update CSSStyleProperties.test.js

Unit test for jsdom/jsdom#3940

Author: asamuzaK

test/CSSStyleProperties.test.js

@@ -1519,4 +1519,12 @@ describe("regression test for https://github.com/jsdom/cssstyle/issues/214", ()
     assert.strictEqual(style.borderWidth, "0.2rem");
     assert.strictEqual(style.border, "");
   });
+
+  it("should get value and priority", () => {
+    const style = new CSSStyleProperties();
+    style.cssText = "word-spacing: 1px !important;";
+    assert.strictEqual(style.cssText, "word-spacing: 1px !important;", "cssText");
+    assert.strictEqual(style.getPropertyValue("word-spacing"), "1px", "value");
+    assert.strictEqual(style.getPropertyPriority("word-spacing"), "important", "priority");
+  });
 });