build: update build-time dependencies, address new warnings (#413)

* build: update build-time dependencies, address new warnings

* build: switch to central repo declaration, remove redundant repositories

* build: use spotless predeclaration, more task avoidance on kotlin modules

cloud-tasks/src/main/java/cloud/commandframework/tasks/TaskRecipe.java

@@ -110,6 +110,7 @@ public final class TaskRecipe {
      * @param <I> Input type
      * @param <O> Output type
      */
+    @SuppressWarnings("UnusedTypeParameter") // already in public API
     public final class TaskRecipeComponentOutputting<I, O> {
 
         private final Object initialInput;