Merge topic 'ci-windows-osmesa-wheels'

1e90386f ci: also exclude line rendering difference tests on OSMesa
6b8cdf97 vtkOSOpenGLRenderWindow: handle `nullptr` for extensions
6a8bc119 wheels: use `delvewheel` for shared library management on Windows
5291aa5a gitlab-ci: use `delvewheel` to build Windows wheels
e7ca4e72 gitlab-ci: add CI jobs for OSMesa wheels on Windows
8396457c ci: add a script to download an OSMesa SDK
2c816eaf vtkOSOpenGLRenderWindow: fix the OSMesa context function type
4c96d605 Merge branch 'upstream-glew' into HEAD
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Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Reviewed-by: Mathieu Westphal <mathieu.westphal@kitware.com>
Tested-by: Bane Sullivan <bane.sullivan@kitware.com>
Merge-request: !10095