Fix NoClassFoundException when EMI was not installed (GregTechCEu#2325)

Author: krossgg

src/main/java/com/gregtechceu/gtceu/api/recipe/ui/GTRecipeTypeUI.java

@@ -257,7 +257,8 @@ public IEditableUI<WidgetGroup, RecipeHolder> createEditableUITemplate(final boo
                                     } else if (LDLib.isEmiLoaded()) {
                                         recipeType.getRecipesByCategory().keySet()
                                                 .forEach(e -> EmiApi
-                                                        .displayRecipeCategory(GTRecipeEMICategory.getCategoryFor(e)));
+                                                        .displayRecipeCategory(
+                                                                GTRecipeEMICategory.CATEGORIES.apply(e)));
                                     }
                                 }
                             }).setHoverTooltips("gtceu.recipe_type.show_recipes"));

src/main/java/com/gregtechceu/gtceu/integration/emi/recipe/GTRecipeEMICategory.java

@@ -31,8 +31,8 @@
 
 public class GTRecipeEMICategory extends EmiRecipeCategory {
 
-    public static final Function<GTRecipeCategory, List<GTEmiRecipe>> CATEGORIES = Util
-            .memoize(category1 -> new ArrayList<>());
+    public static final Function<GTRecipeCategory, GTRecipeEMICategory> CATEGORIES = Util
+            .memoize(GTRecipeEMICategory::getCategoryFor);
     public final GTRecipeType recipeType;
 
     private final GTRecipeCategory category;