[JuliaLowering] Fix break/continue in try (#61525)
Alternative to https://github.com/JuliaLang/julia/pull/61523, fix
https://github.com/JuliaLang/JuliaLowering.jl/issues/171.
Push to `ctx.handler_token_stack` before construction of the
`FinallyHandler`, since the `JumpTarget` constructor needs it. The extra
entry is ignored in `enter_finally_block`'s call to
`emit_leave_handler`, but not in the one in `emit_break`. These changes
should directly match flisp.
I think we're still missing some `pop_exception`s compared to flisp, but
wanted to get this PR up given the other one. As noted in the tests, I
need to port https://github.com/JuliaLang/julia/pull/55876, which
duplicates the finally block and only adds `pop_exception` to one copy.
