Fix tests to automatically get chrome driver path.

Author: lordjabez

tests/test_requestium.py

@@ -1,16 +1,19 @@
 import pytest
 import selenium
+import shutil
 
 import requestium
 
 
+chrome_webdriver_path = shutil.which('chromedriver')
+
 chrome_webdriver = selenium.webdriver.chrome.webdriver.WebDriver()
 firefox_webdriver = selenium.webdriver.firefox.webdriver.WebDriver()
 
 
 session_parameters = [
-    {'webdriver_path': 'chromedriver'},
-    {'webdriver_path': 'chromedriver', 'headless': True},
+    {'webdriver_path': chrome_webdriver_path},
+    {'webdriver_path': chrome_webdriver_path, 'headless': True},
     {'driver': chrome_webdriver},
     {'driver': firefox_webdriver},
 ]