How to drop softDeletes from a table in a migration

On your migration class use dropSoftDeletes():

public function down()
{
    Schema::table("users", function ($table) {
        $table->dropSoftDeletes();
    });
}

This method can be found in Illuminate\Database\Schema\Blueprint.php:

public function dropSoftDeletes()
{
    $this->dropColumn('deleted_at');
}

Since Laravel 5.5, this information can be found in the documentation.