Bug 1911891 - Disable test from browser_groupedBySortPersistence.js on win32 debug builds. r=mkmelin

Differential Revision: https://phabricator.services.mozilla.com/D219500

--HG--
extra : rebase_source : 3e3382563cd5f072820767058bb42c490169e19e
extra : amend_source : 1cac55ed801260e334ac2f3d21a340e48610121f

mail/base/test/browser/browser_groupedBySortPersistence.js

@@ -138,4 +138,9 @@ add_task(async function testSingleVirtual() {
 /** Test a virtual folder with multiple backing folders. */
 add_task(async function testXFVirtual() {
   await subTest(virtualFolderAB);
-});
+}).skip(
+  // Permanent failure on CI, bug 1911891.
+  AppConstants.platform == "win" &&
+    AppConstants.DEBUG &&
+    !Services.appinfo.is64Bit
+);