Better handling when a BE type isn't registered

This should never happen, but apparently it does!? We now log an error
(rather than crashing), and include the original BE (and associated
block), as the BE type isn't very useful.

See #1750. Technically this fixes it, but want to do some more poking
there first.

projects/forge/src/main/java/dan200/computercraft/shared/platform/PlatformHelperImpl.java

@@ -360,6 +360,12 @@ public class PlatformHelperImpl implements PlatformHelper {
             return key;
         }
 
+        @Nullable
+        @Override
+        public ResourceLocation tryGetKey(T object) {
+            return registry.getKey(object);
+        }
+
         @Override
         public T get(ResourceLocation location) {
             var object = registry.getValue(location);