Auto merge of #13416 - vigneshsarma:issue-13408, r=jdm

Replace instances of old ServiceWorker specification URL with new one

<!-- Please describe your changes on the following line: -->

The old specification URL is
https://slightlyoff.github.io/ServiceWorker/spec/service_worker/, which has
been replaced by the new one at https://w3c.github.io/ServiceWorker/.

---
<!-- 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] These changes fix #13408 (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [X] These changes do not require tests because all the changes are in commented parts of the code.

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

The old specification URL is
https://slightlyoff.github.io/ServiceWorker/spec/service_worker/ has
been replaced by the new one at https://w3c.github.io/ServiceWorker/.

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---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/13416)
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components/script/dom/webidls/Client.webidl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#client
+// https://w3c.github.io/ServiceWorker/#client
 
 [Pref="dom.serviceworker.enabled", Exposed=(Window,Worker)]
 interface Client {

components/script/dom/webidls/Navigator.webidl

@@ -33,7 +33,7 @@ interface NavigatorBluetooth {
     readonly attribute Bluetooth bluetooth;
 };
 
-// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#navigator-service-worker
+// https://w3c.github.io/ServiceWorker/#navigator-service-worker
 partial interface Navigator {
   [SameObject, Pref="dom.serviceworker.enabled"] readonly attribute ServiceWorkerContainer serviceWorker;
 };

components/script/dom/webidls/ServiceWorker.webidl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-// http://slightlyoff.github.io/ServiceWorker/spec/service_worker/#service-worker-obj
+// http://w3c.github.io/ServiceWorker/#service-worker-obj
 [Pref="dom.serviceworker.enabled", Exposed=(Window,Worker)]
 interface ServiceWorker : EventTarget {
   readonly attribute USVString scriptURL;

components/script/dom/webidls/ServiceWorkerContainer.webidl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#service-worker-container
+// https://w3c.github.io/ServiceWorker/#service-worker-container
 [Pref="dom.serviceworker.enabled", Exposed=(Window,Worker)]
 interface ServiceWorkerContainer : EventTarget {
   [Unforgeable] readonly attribute ServiceWorker? controller;

components/script/dom/webidls/ServiceWorkerGlobalScope.webidl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#service-worker-global-scope
+// https://w3c.github.io/ServiceWorker/#service-worker-global-scope
 
 [Global=(Worker,ServiceWorker), Exposed=ServiceWorker,
  Pref="dom.serviceworker.enabled"]

components/script/dom/webidls/ServiceWorkerRegistration.webidl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#service-worker-registration-obj
+// https://w3c.github.io/ServiceWorker/#service-worker-registration-obj
 [Pref="dom.serviceworker.enabled", Exposed=(Window,Worker)]
 interface ServiceWorkerRegistration : EventTarget {
   [Unforgeable] readonly attribute ServiceWorker? installing;