ENH: support plugin building for paraview-5.7

Note
    For paraview-5.7 (and later?) plugins are built into their own subdirs.
    It also is not possible to suppress creation of static libraries in
    the process.

The current solution is still a bit ugly
  - install into a local "staged" location (within the build directory)
  - use rsync to relocate to the .so files to the plugin directory
3 jobs for develop
Status Job ID Name Coverage
  Build
failed #367
build

 
  Test
skipped #369
allowed to fail
code_quality
skipped #368
test
 
Name Stage Failure
failed
build Build There has been a timeout failure or the job got stuck. Check your timeout limits or try again
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