Bug 1696042 - [ci] web-platform-test-reftest: Run fission windows10-qr/debug on trunk, r=jgraham

This enables the following configuration on autoland/central:
> test-windows10-64-qr/debug-web-platform-tests-reftest-fis-e10s

Differential Revision: https://phabricator.services.mozilla.com/D110830

taskcluster/ci/test/web-platform.yml

@@ -162,9 +162,8 @@ web-platform-tests-reftest:
         by-variant:
             fission:
                 by-test-platform:
-                    linux.*64-qr/debug: ['trunk']
-                    linux.*64(-shippable)?-qr/opt: ['trunk']
-                    windows10-64(-shippable)?-qr/opt: ['trunk']
+                    (linux.*64|windows10-64)-qr/debug: ['trunk']
+                    (linux.*64|windows10-64)(-shippable)?-qr/opt: ['trunk']
                     default: []
             default: built-projects
     tier: