rrule causes scalar indexing for `repeat`

julia> func(x) = sum(repeat(x, inner = (1, 3)))
func (generic function with 1 method)

julia> func(CUDA.rand(2,3))
7.5995846f0

julia> Zygote.gradient(func,CUDA.rand(2,3))
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 are only permitted from the REPL for prototyping purposes.
If you did intend to index this array, annotate the caller with @allowscalar.
Stacktrace:
  [1] error(s::String)
    @ Base .\error.jl:33
  [2] assertscalar(op::String)
    @ GPUArraysCore C:\Users\Luffy\.julia\packages\GPUArraysCore\rSIl2\src\GPUArraysCore.jl:78
  [3] getindex(::CuArray{Float32, 2, CUDA.Mem.DeviceBuffer}, ::Int64, ::Int64)
    @ GPUArrays C:\Users\Luffy\.julia\packages\GPUArrays\gok9K\src\host\indexing.jl:9
  [4] getindex
    @ C:\Users\Luffy\.julia\packages\GPUArrays\gok9K\src\host\indexing.jl:30 [inlined]
  [5] iterate
    @ .\iterators.jl:245 [inlined]
  [6] (::Zygote.var"#519#525"{Tuple{Int64, Int64}, CuArray{Float32, 2, CUDA.Mem.DeviceBuffer}})(Δ::CuArray{Float32, 2, CUDA.Mem.DeviceBuffer})
    @ Zygote C:\Users\Luffy\.julia\packages\Zygote\IoW2g\src\lib\array.jl:136
  [7] #2693#back
    @ C:\Users\Luffy\.julia\packages\ZygoteRules\AIbCs\src\adjoint.jl:73 [inlined]
  [8] Pullback
    @ .\REPL[15]:1 [inlined]
  [9] (::Zygote.var"#60#61"{typeof(∂(func))})(Δ::Float32)
    @ Zygote C:\Users\Luffy\.julia\packages\Zygote\IoW2g\src\compiler\interface.jl:41
 [10] gradient(f::Function, args::CuArray{Float32, 2, CUDA.Mem.DeviceBuffer})
    @ Zygote C:\Users\Luffy\.julia\packages\Zygote\IoW2g\src\compiler\interface.jl:76
 [11] top-level scope
    @ REPL[17]:1
 [12] top-level scope
    @ C:\Users\Luffy\.julia\packages\CUDA\tTK8Y\src\initialization.jl:52

Reproduce the Julia example with CUDA.rand, repeat, and Zygote.gradient, then follow the stack trace into Zygote's src/lib/array.jl and the related ChainRules behavior. Done means the gradient path no longer triggers scalar indexing for this GPU-array repeat case, with a regression test covering the example.