patch 9.0.1972: win32: missing '**' expansion test

patch 9.0.1972: win32: missing '**' expansion test

Problem:  win32: missing '**' expansion test (after v9.0.1947)
Solution: Add test for MS-Windows

win32: Add "**" test

Vim supports "**" on MS-Windows. However, it is not tested by
`Test_glob_extended_bash`.

Unlike Unix, it doesn't use 'shell' and doesn't support {,} expansion.
So, I added as a separate test.

related: #13205
closes: #13250

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Ken Takata <kentkt@csc.jp>