Multi-axis concatenation errors on 1.12

Trying to concatenate multiple arrays using square bracket syntax errors on 1.12. After descending with Cthulhu.jl and comparing with Julia master, I'm seeing it may be related to https://github.com/JuliaLang/julia/pull/39729

## MWE

Julia v1.11.7:

```julia
julia> v = CUDA.zeros(1); [v v; v v]
2×2 CuArray{Float32, 2, CUDA.DeviceMemory}:
0.0 0.0
0.0 0.0
```

Julia v1.12.3:

```julia
julia> v = CUDA.zeros(1); [v v; v v]
ERROR: Scalar indexing is disallowed.
Invocation of getindex resulted in scalar indexing of a GPU array.
This is typically caused by calling an iterating implementation of a method.
Such implementations *do not* execute on the GPU, but very slowly on the CPU,
and therefore should be avoided.

If you want to allow scalar iteration, use `allowscalar` or `@allowscalar`
to enable scalar iteration globally or for the operations in question.
Stacktrace:
[1] error(s::String)
@ Base ./error.jl:44
[2] errorscalar(op::String)
@ GPUArraysCore ~/.julia/packages/GPUArraysCore/aNaXo/src/GPUArraysCore.jl:151
[3] _assertscalar(op::String, behavior::GPUArraysCore.ScalarIndexing)
@ GPUArraysCore ~/.julia/packages/GPUArraysCore/aNaXo/src/GPUArraysCore.jl:124
[4] assertscalar(op::String)
@ GPUArraysCore ~/.julia/packages/GPUArraysCore/aNaXo/src/GPUArraysCore.jl:112
[5] getindex
@ ~/.julia/packages/GPUArrays/0F4Dn/src/host/indexing.jl:50 [inlined]
[6] iterate
@ ./abstractarray.jl:1235 [inlined]
[7] iterate
@ ./abstractarray.jl:1233 [inlined]
[8] hvncat_fill!(A::CuArray{Float32, 2, CUDA.DeviceMemory}, scratch1::Vector{Int64}, scratch2::Vector{Int64}, d1::Int64, d2::Int64, as::NTuple{4, CuArray{Float32, 1, CUDA.DeviceMemory}})
@ Base ./abstractarray.jl:2723
[9] _typed_hvncat_dims(::Type{Float32}, dims::Tuple{Int64, Int64}, row_first::Bool, as::NTuple{4, CuArray{Float32, 1, CUDA.DeviceMemory}})
@ Base ./abstractarray.jl:2613
[10] _typed_hvncat(::Type, ::Tuple{Int64, Int64}, ::Bool, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::Vararg{CuArray{Float32, 1, CUDA.DeviceMemory}})
@ Base ./abstractarray.jl:2520
[11] typed_hvncat(::Type, ::Tuple{Int64, Int64}, ::Bool, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::Vararg{CuArray{Float32, 1, CUDA.DeviceMemory}})
@ Base ./abstractarray.jl:2351
[12] typed_hvcat(::Type{Float32}, ::Tuple{Int64, Int64}, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::Vararg{CuArray{Float32, 1, CUDA.DeviceMemory}})
@ Base ./abstractarray.jl:2193
[13] hvcat_internal(::Tuple{Int64, Int64}, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::Vararg{CuArray{Float32, 1, CUDA.DeviceMemory}})
@ SparseArrays ~/.julia/juliaup/julia-1.12.3+0.x64.linux.gnu/share/julia/stdlib/v1.12/SparseArrays/src/sparsevector.jl:1285
[14] hvcat(::Tuple{Int64, Int64}, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::CuArray{Float32, 1, CUDA.DeviceMemory}, ::Vararg{CuArray{Float32, 1, CUDA.DeviceMemory}})
@ SparseArrays ~/.julia/juliaup/julia-1.12.3+0.x64.linux.gnu/share/julia/stdlib/v1.12/SparseArrays/src/sparsevector.jl:1289
[15] top-level scope
@ REPL[3]:1
```