The module Algolia_AlgoliaSearchInventory has been develop to provide compatibility between Magento 2.3 Inventory feature and Algolia Search 1.12+ extension.
The easiest way to install the extension is to use Composer
Run the following commands:
$ composer require algolia/algoliasearch-inventory-magento-2$ bin/magento module:enable Algolia_AlgoliaSearchInventory$ bin/magento setup:upgrade && bin/magento setup:static-content:deploy