chore: import upstream snapshot with attribution

tests/unit/classes/deprecated_spec.js

@@ -0,0 +1,15 @@
+const deprecated = require("../../../js/deprecated");
+
+describe("Deprecated", () => {
+	it("should be an object", () => {
+		expect(typeof deprecated).toBe("object");
+	});
+
+	it("should contain clock array with deprecated options as strings", () => {
+		expect(Array.isArray(["deprecated.clock"])).toBe(true);
+		for (let option of deprecated.configs) {
+			expect(typeof option).toBe("string");
+		}
+		expect(deprecated.clock).toEqual(expect.arrayContaining(["secondsColor"]));
+	});
+});