Add correct index on visits potential_bot column

data/migrations/Version20230303164233.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ShlinkMigrations;
+
+use Doctrine\DBAL\Platforms\MySQLPlatform;
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20230303164233 extends AbstractMigration
+{
+    private const INDEX_NAME = 'visits_potential_bot_IDX';
+
+    public function up(Schema $schema): void
+    {
+        $visits = $schema->getTable('visits');
+        $this->skipIf($visits->hasIndex(self::INDEX_NAME));
+
+        $visits->dropIndex('IDX_visits_potential_bot'); // Old index
+        $visits->addIndex(['potential_bot'], self::INDEX_NAME);
+    }
+
+    public function isTransactional(): bool
+    {
+        return ! ($this->connection->getDatabasePlatform() instanceof MySQLPlatform);
+    }
+}