Mark `numeric-types.rs` as 64-bit only for now

This is to unblock the tree, a proper fix will need to be investigated.
I think the debuginfo test suite supports revisions, however debugger
directives do not respect such revisions, which is problematic.

It's that 32-bit and 64-bit msvc of course have different integer widths
for `isize` and `usize`, meaning their underlying integer is different
and thus printed differently.