fix: default to shardy again

[avik-pal]

fixes #1472

[wsmoses]

Sharding Constraint: Error During Test at /home/runner/work/Reactant.jl/Reactant.jl/test/sharding.jl:192
  Got exception outside of a @test
  INVALID_ARGUMENT: Shardy export for HLO round trip failed;
  
  Detailed error from MLIR: /home/runner/work/Reactant.jl/Reactant.jl/src/Ops.jl:2658:0: error: 'sdy.reshard' op unknown mesh: @mesh
  /home/runner/work/Reactant.jl/Reactant.jl/src/Ops.jl:2658:0: note: see current operation: %2 = "sdy.reshard"(%1) <{sharding = #sdy.sharding<@mesh, [{"model"}, {}]>}> : (tensor<4x4xf32>) -> tensor<4x4xf32>