Update reference platform to Ubuntu Jammy

The upcoming Ubuntu Jammy provides updated versions of the dependencies.

Open tasks:

Fix test: ae108-examples-GeneralizedNonlinearSolver yields DIVERGED_LINEAR_SOLVE
Install/ask for PETSc/SLEPc version 3.15.5 on Euler
PETSc/SLEPc 3.15 available on Euler
Test HDF5 output and XDMF generation

Edited Jun 16, 2022 by webmanue

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