update poetry certifi version and update tests failing due to mpi-ser…

[jedwards4b]

Fixes issue #65

[peverwhee]

Thanks @jedwards4b !

I got this error trying to run a test on izumi:

  File "/home/courtneyp/Projects/sima-init-const/bin/git-fleximod", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/home/courtneyp/Projects/sima-init-const/.lib/git-fleximod/git_fleximod/git_fleximod.py", line 348, in main
    submodules_update(gitmodules, root_dir, fxrequired, force)
  File "/home/courtneyp/Projects/sima-init-const/.lib/git-fleximod/git_fleximod/git_fleximod.py", line 244, in submodules_update
    submod.update()
  File "/home/courtneyp/Projects/sima-init-const/.lib/git-fleximod/git_fleximod/submodule.py", line 344, in update
    self.sparse_checkout()
  File "/home/courtneyp/Projects/sima-init-const/.lib/git-fleximod/git_fleximod/submodule.py", line 224, in sparse_checkout
    gitroot = self.root_dir.strip()
              ^^^^^^^^^^^^^^^^^^^
AttributeError: 'PosixPath' object has no attribute 'strip'

If I changed that line (224) in submodule.py to gitroot = self.root_dir, it worked.

[jedwards4b]

@peverwhee Please try again.

[peverwhee]

fixes my issue! thanks!