Do not manipulate sys.path in tests

Author: akx

tests/database_test.py

@@ -4,11 +4,8 @@
 from __future__ import unicode_literals
 
 import ipaddress
-import sys
 import unittest
 
-sys.path.append("..")
-
 import geoip2.database
 import geoip2.errors
 import maxminddb

tests/models_test.py

@@ -7,8 +7,6 @@
 from typing import Dict
 import unittest
 
-sys.path.append("..")
-
 import geoip2.models
 
 

tests/webservice_test.py

@@ -4,8 +4,6 @@
 import asyncio
 import copy
 import ipaddress
-import json
-import sys
 from typing import cast, Dict
 import unittest
 from pytest_httpserver import HeaderValueMatcher
@@ -14,7 +12,6 @@
 from collections import defaultdict
 
 
-sys.path.append("..")
 import geoip2
 from geoip2.errors import (
     AddressNotFoundError,