Win deploy: Boost Regex is header-only since 1.77

[Malinero]

same as https://github.com/monero-project/monero/blob/master/CMakeLists.txt#L1048

[selsta]

While the patch itself looks good, why is this needed? Is deploy currently broken?

1.77 came out a while ago.

[Malinero]

I think it's currently broken. I don't have a windows, but while trying to debug the windows CI on #4407, I saw this https://github.com/Malinero/monero-gui/actions/runs/13379636601/job/37365795118#step:4:761

Result of :

        foreach(ITEM ${WIN_DEPLOY_DLLS})
            find_file(${ITEM}_VAR ${ITEM} REQUIRED)
        endforeach()

[selsta]

Not sure why this only broke now.

[tobtoht]

Not sure why this only broke now.

MSYS2 used to ship a static compatibility library and stopped doing that a few months ago.