Update Lib/test/test_mimetypes.py

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Author: clin1234

Lib/test/test_mimetypes.py

@@ -237,9 +237,7 @@ def check_extensions():
                 ("application/vnd.apple.mpegurl", ".m3u"),
                 ("application/vnd.ms-excel", ".xls"),
                 ("application/vnd.ms-fontobject", ".eot"),
-                ("application/vnd.ms-htmlhelp", ".chm"),
                 ("application/vnd.ms-powerpoint", ".ppt"),
-                ("application/vnd.ms-officetheme", ".thmx"),
                 ("application/vnd.oasis.opendocument.graphics", ".odg"),
                 ("application/vnd.oasis.opendocument.presentation", ".odp"),
                 ("application/vnd.oasis.opendocument.spreadsheet", ".ods"),