hypre3d test fails

[dschwoerer]

In CI the hypre3d test started failing.

I am not sure what changed, but the new tolerance is around 1e-4 when it was 1e-6.

Maybe worth to fix for #3084 ?

[dschwoerer]

Ah, it seems hypre now uses some non-initialised memory.

So that should be fixable, by someone who knows the hypre solver ...