closes mailchimp#1347 magento 2.3

Setup/Uninstall.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace Ebizmarts\MailChimp\Setup;
+
+use Magento\Framework\Setup\ModuleContextInterface;
+use Magento\Framework\Setup\SchemaSetupInterface;
+use Magento\Framework\Setup\UninstallInterface;
+
+class Uninstall implements UninstallInterface
+{
+    public function uninstall(SchemaSetupInterface $setup, ModuleContextInterface $context)
+    {
+        $tables = [
+            'mailchimp_sync_batches',
+            'mailchimp_errors',
+            'mailchimp_sync_ecommerce',
+            'mailchimp_stores',
+            'mailchimp_webhook_request',
+            'mailchimp_interest_group'
+        ];
+        $tablesFields = [
+            'sales_order' => [
+                'mailchimp_abandonedcart_flag',
+                'mailchimp_campaign_id',
+                'mailchimp_landing_page',
+                'mailchimp_flag'
+            ],
+            'quote' => [
+                'mailchimp_abandonedcart_flag',
+                'mailchimp_campaign_id',
+                'mailchimp_landing_page'
+            ],
+            'sales_order_grid' => [
+                'mailchimp_flag'
+            ]
+        ];
+        $installer = $setup;
+        $installer->startSetup();
+        $connection = $installer->getConnection();
+        foreach ($tables as $table) {
+            $connection->dropTable($setup->getTable($table));
+        }
+        foreach($tablesFields as $table => $columnArray) {
+            foreach($columnArray as $column) {
+                $connection->dropColumn( $setup->getTable($table), $column);
+            }
+        }
+
+        $installer->endSetup();
+    }
+}