make MPI tests work on any number of MPI tasks

15 jobs for generalize_mpi_tests in 20 minutes and 59 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Static Checks
passed #1400812
check_no_asserts

00:00:15

 
  Build Docker
passed #1400813
build_docker_from_cache

00:00:14

 
  Test
passed #1400815
test_mpi

00:00:33

passed #1400814
test_serial

00:09:18

85.0%
 
  Demo Runs
passed #1400823
run_bernoulli

00:00:31

passed #1400824
run_curve_fitting

00:00:29

passed #1400822
run_getting_density

00:08:40

passed #1400818
run_getting_started_1

00:00:35

passed #1400819
run_getting_started_2

00:00:55

passed #1400820
run_getting_started_3

00:06:01

passed #1400821
run_getting_started_mf

00:07:51

passed #1400816
run_ipynb0

00:01:28

passed #1400817
run_ipynb1

00:01:34

passed #1400826
run_meanfield

00:01:43

passed #1400825
run_visual_vi

00:11:09