vtkModule: fix relative path usage within a project

Just matching ../ runs into trouble when a project adds module files in the project, but outside of the current source directory. Normalize paths before detecting ../ components.

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See: paraview/paraview#21388 (closed)
Backport: release

requested review from @mwestphal

assigned to @ben.boeckel

changed milestone to %9.2

Warnings:

• please consider adding a changelog entry in a file ending with .md in Documentation/release/dev.

The warnings do not need to be fixed, but it is recommended to do so.

Warnings:

• please consider adding a changelog entry in a file ending with .md in Documentation/release/dev.

The warnings do not need to be fixed, but it is recommended to do so.

changed the description

mentioned in merge request !9318 (merged)

+1, thanks

Tested as part of ParaView locally too.

Do: merge

merged

mentioned in commit dfc964b3

mentioned in commit 8f30091a

mentioned in merge request paraview/paraview!5785 (merged)

mentioned in merge request !9358 (merged)