How to find problem mirrors for Windows msys2 packages when building PRs

[phunkyfish]

If windows packages are failing a lot it is likely it's a kodi mirror involving the msys2 packages.

First add a temp commit adding the verbose flag -v to the curl command in both these files:

• depends/windows/mingw/03-use-curl.patch
• depends/windowsstore/mingw/03-use-curl.patch

Then go the log and search for Transfer returned error. The mirror listed prior to this will be the problem mirror. Check a few more to be sure.