When a git submodule repository name includes a space character, the git plugin versions through at least git plugin 4.0.0 ignore the submodule.

Problem was found by the plugin pom 3.36 extension which includes a space character in the temporary directories created by the Jenkins test harness.

For example, I defined a repository ssh://home.markwaite.net/~/git/bare/bugs/without-space.git which includes a submodule from ssh://home.markwaite.net/~/git/bare/bugs/with space.git. I can clone the without-space repository from the command line and can update the submodule. When I perform the same operation from a Jenkins job, the repository is cloned, but the submodule is not detected and never updates.