[py] Making path to selenium server independent of the current working dir

Cr-Mirrored-From: https://chromium.googlesource.com/external/github.com/SeleniumHQ/selenium
Cr-Mirrored-Commit: 4e102f670ff2b218282073501919e79e1db48c79
diff --git a/conftest.py b/conftest.py
index b8803d1..ec89ada 100644
--- a/conftest.py
+++ b/conftest.py
@@ -189,7 +189,8 @@
 
     _host = 'localhost'
     _port = 4444
-    _path = '../bazel-bin/java/server/src/org/openqa/selenium/grid/selenium_server_deploy.jar'
+    _path = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))),
+                         'bazel-bin/java/server/src/org/openqa/selenium/grid/selenium_server_deploy.jar')
 
     def wait_for_server(url, timeout):
         start = time.time()