Remove unused import from error_handler.py

Removed unused import of Sequence from collections.abc.

Author: zrekryu

pyrogram/handlers/error_handler.py

@@ -16,7 +16,6 @@
 #  You should have received a copy of the GNU Lesser General Public License
 #  along with Pyrogram.  If not, see <http://www.gnu.org/licenses/>.
 
-from collections.abc import Sequence
 from typing import Callable, Optional, Sequence, Union
 
 import pyrogram