test: add test for MPI_Barrier

[gxyd]

No description provided.

[adit4443ya]

If this PR is intended only for test then it's okay to merge
But if it's for removing barrier wrapper
Then for that i made a patch which i used but encountered an error in the lfortran while gfortran works well for which i opened an issue in here lfortran/lfortran#6720

[adit4443ya]

BTW That issue is the promiment issue which must be resolved as we use comm_f as an argument in so many subroutines and for all of them we use MPI_Comm_f2c
and for that we need that converter function properly working, that is we hshould catch type(c_ptr) correctly as the return value from the BIND(C) function , so i guess we should probably fix that issue in lfortran and then move forward
CC:@gxyd
Issue lfortran/lfortran#6720

[gxyd]

Then for that i made a patch which i used but encountered an error in the lfortran while gfortran works well for which i opened an issue in here lfortran/lfortran#6720

Can you send a PR against this repo with that? That will allow us to see which tests (if any) that fail.

[gxyd]

I'm merging this PR to just allow us to have a test case with MPI_Barrier.

[adit4443ya]

Can you send a PR against this repo with that? That will allow us to see which tests (if any) that fail.

ITs in here #37