[tlbuild] branch2025 tl rebuild please

[Karl Berry]

    >   svn co svn://tug.org/texlive/branches/branch2018/Build/source .

    s/branch2018/branch2025/ ?

For sure :). Sorry. Thanks for doing the update.

Ken and Mojca: if either of you are up for building from the branch, I
believe cygwin and x86_64-darwinlegacy are the only platforms left
un-updated. Who knows if there are any users of those binaries needing
integral signs, but maybe ...

Thanks,
Karl