Tests

Improve parallel boundary regions #3537

Job	Run time
CUDA	12m 15s
Fedora	18m 35s
CMake, PETSc unreleased, ADIOS	23m 43s
Default options, Ubuntu 20.04	16m 50s
Optimised, static	20m 59s
Debug, shared	24m 43s
Shared, release, Ubuntu 20.04	17m 15s
Shared, OpenMP, 3D metrics	15m 1s
CMake, new PETSc	17m 1s
Coverage	14m 1s
	3h 0m 23s

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