Merge topic 'fix-missing-include'

1a5e202a add missing string include.

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: David E. DeMarle <dave.demarle@kitware.com>
Acked-by: Shawn Waldon <shawn.waldon@kitware.com>
Merge-request: !4494
17 jobs for master in 0 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  External
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passed vtk@master-bigmac-osx-shared-debug+clang+python+vtkm

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passed vtk@master-duma-linux-shared-release+ospray

passed vtk@master-eeloo-linux-shared-release+extdeps+java+mpi+python+python3+qt+tbb+vtkm

passed vtk@master-eeloo-linux-shared-release+mpi+nogl

canceled vtk@master-luigi-linux-shared-release+mpi+python+tbb

canceled vtk@master-mun-windows-shared-release+kits+mpi+python+python3+qt+tbb

canceled vtk@master-mun-windows-shared-release+mpi+python+python3+tbb+vtkm

canceled vtk@master-mun-windows-static-release+mpi+python+python3+qt+tbb

canceled vtk@master-taanab-linux-shared-release+mpi+python

canceled vtk@master-trey-osx-shared-release+python+python3+qt

passed vtk@master-adora-linux-shared-release+gcc+mpi+python+qt+tbb+vtkm

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passed vtk@master-bigmac-osx-shared-debug+clang+python+vtkm

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passed vtk@master-duma-linux-shared-release+ospray

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passed vtk@master-eeloo-linux-shared-release+extdeps+java+mpi+python+python3+qt+tbb+vtkm

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passed vtk@master-eeloo-linux-shared-release+mpi+nogl

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