[nested-grid] Fix theme application

For day8/rf8.day8.com.au#312 (comment)

Author: kimo-k

src/re_com/nested_grid.cljs

@@ -1152,6 +1152,7 @@
                                            :children row-header-cells}})
             cells                      (u/part cell-grid-container
                                          {:part  ::cell-grid-container
+                                                :theme theme
                                           :props {:style    {:max-height            max-height
                                                              :max-width             max-width
                                                              :display               :grid