In the GraphQL Admin API, we're deprecating the inventoryAdjustQuantity and inventoryBulkAdjustQuantityAtLocation mutations.
Instead, you can use the new inventoryAdjustQuantities or inventoryMoveQuantities mutations instead.
This is a companion discussion topic for the original entry at https://shopify.dev/changelog/deprecating-mutations-inventoryadjustquantity-and-inventorybulkadjustquantityatlocation