Sets the Git user name and email address used by subsequent Steps in the Workflow.
Sets the global Git identity (user.name and user.email) on the build machine, so every subsequent Step that creates Git commits or tags uses it as the author.
Both values are written to the global Git config (git config --global), so they apply to every repository on the build machine for the rest of the build.
If commits created by later Steps still show a different author, check whether the repository's local Git config or the Step creating the commit overrides user.name or user.email. Local Git config takes precedence over the global one set by this Step.