docs: fix GgitDiffDelta
docs: fix GgitDiffDelta

chergert/libgit2-glib,GNOME/libgit2-glib,weynhamz/GNOME-libgit2-glib,weynhamz/GNOME-libgit2-glib,chergert/libgit2-glib,chergert/libgit2-glib,weynhamz/GNOME-libgit2-glib,GNOME/libgit2-glib,weynhamz/GNOME-libgit2-glib