WIP: Fix Windows CI

[jhale]

cl.exe compilation fails referring to issue in ordering.cpp

D:\a\dolfinx\dolfinx\dolfinx\cpp\dolfinx\graph\ordering.cpp(214,15): error C2676: binary '[': '_Ty' does not define this operator or a conversion to a type acceptable to the predefined operator [D:\a\dolfinx\dolfinx\dolfinx\build-dir\dolfinx\dolfinx.vcxproj]
D:\a\dolfinx\dolfinx\dolfinx\cpp\dolfinx\graph\ordering.cpp(214,15): error C2676:         with [D:\a\dolfinx\dolfinx\dolfinx\build-dir\dolfinx\dolfinx.vcxproj]
D:\a\dolfinx\dolfinx\dolfinx\cpp\dolfinx\graph\ordering.cpp(214,15): error C2676:         [ [D:\a\dolfinx\dolfinx\dolfinx\build-dir\dolfinx\dolfinx.vcxproj]
D:\a\dolfinx\dolfinx\dolfinx\cpp\dolfinx\graph\ordering.cpp(214,15): error C2676:             _Ty=std::array<int,2> [D:\a\dolfinx\dolfinx\dolfinx\build-dir\dolfinx\dolfinx.vcxproj]
D:\a\dolfinx\dolfinx\dolfinx\cpp\dolfinx\graph\ordering.cpp(214,15): error C2676:         ] [D:\a\dolfinx\dolfinx\dolfinx\build-dir\dolfinx\dolfinx.vcxproj]

Line 214 is lvp[w][0] = i; where lvp is a std::vector of std::array<int, 2> and w is an int. Looks completely fine to me and compiles in GCC and clang without issue (and, previous versions of cl.exe).

https://github.com/FEniCS/dolfinx/blob/main/cpp/dolfinx/graph/ordering.cpp#L213