add transportation group to container and vault (#4499)

this allows for them to be placed over belts so that people no longer have to clear an area around the core when placing vaults around it.

core/src/mindustry/content/Blocks.java

@@ -1399,6 +1399,7 @@ public class Blocks implements ContentList{
             size = 3;
             itemCapacity = 1000;
             flags = EnumSet.of(BlockFlag.storage);
+            group = BlockGroup.transportation;
         }};
 
         container = new StorageBlock("container"){{
@@ -1406,6 +1407,7 @@ public class Blocks implements ContentList{
             size = 2;
             itemCapacity = 300;
             flags = EnumSet.of(BlockFlag.storage);
+            group = BlockGroup.transportation;
         }};
 
         unloader = new Unloader("unloader"){{