[bazel] Add an :all target to binary repos

[attilaolah]

This is the simplest solution to my problem described in #1294.

I'm happy to change this to something more specific, e.g. by exporting only the files I currently need, but it seems like having an :all target is the most future-proof way here.

Closes #1294.

[kripken]

Test error is not related and should not block this landing.

@tlively the error is in recent Lattice code in Binaryen,

In file included from /root/project/binaryen/main/src/tools/wasm-fuzz-lattices.cpp:21:0:
/usr/include/c++/7/variant: In instantiation of 'constexpr const size_t std::variant_size_v<wasm::RandomFullLattice::L>':
/usr/include/c++/7/variant:702:10:   required from 'struct std::__detail::__variant::__gen_vtable<wasm::RandomFullLattice::ElementImpl, wasm::RandomFullLattice::getBottom() const::<lambda(const auto:5&)>&&, wasm::RandomFullLattice::L&>'
/usr/include/c++/7/variant:1255:23:   required from 'constexpr decltype(auto) std::visit(_Visitor&&, _Variants&& ...) [with _Visitor = wasm::RandomFullLattice::getBottom() const::<lambda(const auto:5&)>; _Variants = {wasm::RandomFullLattice::L&}]'
/root/project/binaryen/main/src/tools/wasm-fuzz-lattices.cpp:666:29:   required from here
/usr/include/c++/7/variant:97:29: error: incomplete type 'std::variant_size<wasm::RandomFullLattice::L>' used in nested name specifier
     inline constexpr size_t variant_size_v = variant_size<_Variant>::value;
                             ^~~~~~~~~~~~~~