fix weak scaling of wave equation

[lslusarczyk]

Weak scaling of wave equation goes too high in plots (stencil2d has problems and third one too). Check why. For 2D benchmarks vector_size is not used. Wave_equation problem size is too small (4k, should be probably 16k), but let's also lower num of items.

We want to have all plots from Ben's paper be automated.

It is very difficult to make reference wave equation implementation - it is todo but with low priority.

Monitor devcloud action in github (and borealis action in priv CI repo -> look for logs in cmake-output file of 'summary' and artifacts).

Fix sort which probably causes timeout. Improve logs of benchmarking.

Understand changes made in performance repo.