According to https://medium.com/@maryam.ghani160/how-to-ignore-changes-in-git-submodules-a3ea1463bdde you can

git config submodule.{yourModulePath}.ignore all

or change you .gitmodule to

[submodule "test"]
   path = test
   url = git@github:maloochpich/test.git
   branch = master
   ignore = dirty