git: add alias for git stash --include-untracked (#8617)

plugins/git/README.md

@@ -154,6 +154,7 @@ plugins=(... git)
 | gstl                 | git stash list                                                                                                                |
 | gstp                 | git stash pop                                                                                                                 |
 | gsts                 | git stash show --text                                                                                                         |
+| gstu                 | git stash --include-untracked                                                                                                 |
 | gstall               | git stash --all                                                                                                               |
 | gsu                  | git submodule update                                                                                                          |
 | gsw                  | git switch                                                                                                                    |

plugins/git/git.plugin.zsh

@@ -236,6 +236,7 @@ alias gstd='git stash drop'
 alias gstl='git stash list'
 alias gstp='git stash pop'
 alias gsts='git stash show --text'
+alias gstu='git stash --include-untracked'
 alias gstall='git stash --all'
 alias gsu='git submodule update'
 alias gsw='git switch'