bump polkavm-x deps to 0.4.0
Follow up from #2347 this time to verify that fixtures build to RISC-V --------- Co-authored-by: alvicsam <alvicsam@gmail.com> Co-authored-by: Alexander Samusev <41779041+alvicsam@users.noreply.github.com> Co-authored-by: Alexander Theißen <alex.theissen@me.com>