Remove canClickRunClientCommand

This was added in 4675583e1c to handle
Forge on longer supporting RUN_COMMAND for client-side commands.
However, the mixins are still present on NF/1.20.4, so we don't need
this!

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

@@ -312,11 +312,6 @@ public class PlatformHelperImpl implements PlatformHelper {
         return event.getUseItem() == Event.Result.DENY ? InteractionResult.PASS : stack.useOn(context);
     }
 
-    @Override
-    public boolean canClickRunClientCommand() {
-        return false;
-    }
-
     private record RegistrationHelperImpl<R>(DeferredRegister<R> registry) implements RegistrationHelper<R> {
         @Override
         public <T extends R> RegistryEntry<T> register(String name, Supplier<T> create) {