tests/qtest: migration-test: Skip running some TLS cases for win32

tests/qtest: migration-test: Skip running some TLS cases for win32

Some migration test cases use TLS to communicate, but they fail on
Windows with the following error messages:

  qemu-system-x86_64: TLS handshake failed: Insufficient credentials for that request.
  qemu-system-x86_64: TLS handshake failed: Error in the pull function.
  query-migrate shows failed migration: TLS handshake failed: Error in the pull function.

Disable them temporarily.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Message-Id: <20220925113032.1949844-51-bmeng.cn@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>