Bug 1647291 - Add "ie" to localization comment for browser data types r=Gijs,fluent-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D80445

browser/locales/en-US/browser/migration.ftl

@@ -103,6 +103,7 @@ imported-edge-reading-list = Reading List (From Edge)
 ## chrome
 ## edge
 ## firefox
+## ie
 ## safari
 ## The various beta and development versions of edge and chrome all get
 ## normalized to just "edge" and "chrome" for these strings.