Exclude VTK Web modules from VTK_BUILD_ALL_MODULES

VTK Web has a dependence on Python wrapping which is not required
for VTK_BUILD_ALL_MODULES, so exclude it from this list.

Change-Id: I887b2a8d2bac14fa60e06163becf1bce7cac84ae
Merge topic 'exclude-vtkweb-from-build-al' into master

c4c595a4 Exclude VTK Web modules from VTK_BUILD_ALL_MODULES