Describe the bug

I get this error when I try to add this code:

private void registerUpgradeMappings() {
    RefinedStorageApi.INSTANCE.getUpgradeRegistry().forDestination(UpgradeDestinations.ADVANCED_IMPORTER)
        .add(Items.INSTANCE.getSpeedUpgrade(), 4)
        .add(Items.INSTANCE.getStackUpgrade())
        .add(Items.INSTANCE.getRegulatorUpgrade(), 4);
}

How can we reproduce this bug or crash?

.

What Minecraft version is this happening on?

Minecraft 1.21.1

What NeoForge or Fabric version is this happening on?

NeoForge - 21.1.115

What Refined Storage version is this happening on?

2.0.0-beta.1

Relevant log output