Comment réparer MySQL: la taille de la colonne d'index trop grande (Laravel migrate)

//Laravel located in config/database.php
//replace this one in mysql
    'charset' => 'utf8mb4',
    'collation' => 'utf8mb4_unicode_ci',
            
//to this one
    'charset'   => 'utf8',
    'collation' => 'utf8_unicode_ci',
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