code: public function dropPrimaryKey($name, $table)
      {
          $sql = $this->db->getQueryBuilder()->dropPrimaryKey($name, $table);
  
          return $this->setSql($sql)->requireTableSchemaRefresh($table);
      }
docs: Creates a SQL command for removing a primary key constraint to an existing table.
  @param string $name the name of the primary key constraint to be removed.
  @param string $table the table that the primary key constraint will be removed from.
  @return $this the command object itself