Auto merge of #19559 - tigercosmos:t1, r=KiChjang

implement valid week string

<!-- Please describe your changes on the following line: -->
implement valid week string
part of #19172

r? @KiChjang

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/19559)
<!-- Reviewable:end -->

tests/wpt/web-platform-tests/html/semantics/forms/the-input-element/week.html

@@ -17,6 +17,9 @@
     {value: "2014W", expected: "", testname: "Invalid value: no week number"},
     {value: "2014W52", expected: "", testname: "Invalid value: no '-' (U+002D)"},
     {value: "-W52", expected: "", testname: "Invalid value: yearless week"},
+    {value: "2017-w52", expected: "", testname: "Invalid value: should be capital letter 'W'"},
+    {value: "2017-W52-", expected: "", testname: "Invalid value: incorrect with '-' at the end"},
+    {value: "2017-W52-12", expected: "", testname: "Invalid value: value should be two parts"},
     {value: "W52", expected: "", testname: "Invalid value: yearless week and no '-' (U+002D)"},
     {value: "2014-W03", attributes: { min: "2014-W02" }, expected: "2014-W03", testname: "Value >= min attribute"},
     {value: "2014-W01", attributes: { min: "2014-W02" }, expected: "2014-W01", testname: "Value < min attribute"},