Allow passing custom `configure` options?

[fingolfin]

I've been doing

      - name: "Install NormalizInterface"
        uses: gap-actions/install-pkg@v1
        with:
          packages: gap-packages/NormalizInterface@devel

but this builds its own copy of normaliz. But I can do sudo apt install libnormaliz-dev and then do ./configure --with-normaliz=/usr/local to build it against the system normaliz -- which shaves off some precious compile time.

So it would be nice if I could somehow tell gap-actions/install-pkg to use this extra configure flag.

Of course in this case one can argue "why don't you just detect and use the system installed normaliz" -- and maybe that's what it should do (I've been contemplating this since 2018). But for now it just doesn't.

But there may be other packages were there are configure options that one really needs to specify. Say I might need to specify a --enable-debug flag, or --disable-avx or stuff like that.

Also related: gap-packages/NormalizInterface#124

[stertooy]

This action doesn't build the package, it just downloads it and puts it in the correct place. I guess calling this action install-pkg was a bit of a mistake... the name is certainly misleading.

Building is done by the build-pkg action, which has a configflags input. So that should work, at least in NormalizInterface's own CI tests. But if you need this as part of another package's CI tests, that's a bit more difficult, and I don't immediately see a good solution...