Bug 1821918 - Increase the number of chunks for windows debug web-platform tests due to hitting max run time. r=jmaher

Differential Revision: https://phabricator.services.mozilla.com/D172904

taskcluster/ci/test/web-platform.yml

@@ -50,7 +50,7 @@ web-platform-tests:
             linux.*/debug: 16
             macosx.*/debug: 18
             windows.*32.*/opt: 12
-            windows.*/debug: 14
+            windows.*/debug: 16
             windows.*-ccov.*/opt: 14
             default: 10
     max-run-time: