bpo-40443: Remove unused imports in the zoneinfo (GH-20354)

(cherry picked from commit 3436f5f)

Co-authored-by: Dong-hee Na <donghee.na92@gmail.com>

Author: miss-islington

Lib/zoneinfo/_tzpath.py

@@ -1,5 +1,4 @@
 import os
-import sys
 import sysconfig
 
 

Lib/zoneinfo/_zoneinfo.py

@@ -2,10 +2,7 @@
 import calendar
 import collections
 import functools
-import os
 import re
-import struct
-import sys
 import weakref
 from datetime import datetime, timedelta, timezone, tzinfo