docs(pytest plugin) Document new fixtures

Author: tony

docs/pytest-plugin.md

@@ -37,7 +37,7 @@ This pytest plugin works by providing {ref}`pytest fixtures <pytest:fixtures-api
 
 ## Recommended Fixtures
 
-When the plugin is enabled and `pytest` is run, these fixtures are automatically used:
+When the plugin is enabled and `pytest` is run, these overridable fixtures are automatically used:
 
 - Create temporary test directories for:
   - `/home/` ({func}`home_path`)
@@ -50,6 +50,11 @@ When the plugin is enabled and `pytest` is run, these fixtures are automatically
 - Set default VCS configurations:
   - Use {func}`hgconfig` for [`HGRCPATH`] via {func}`set_hgconfig`
   - Use {func}`gitconfig` for [`GIT_CONFIG`] via {func}`set_gitconfig`
+- Set default commit names and emails:
+  - Name: {func}`vcs_name`
+  - Email: {func}`vcs_email`
+  - User (e.g. _user <email@tld>_): {func}`vcs_user`
+  - For git only: {func}`git_commit_envvars`
 
 These ensure that repositories can be cloned and created without unnecessary warnings.