Test runner: remove noisy debug output.

tools/test-server.py

Index: tools/test-server.py
diff --git a/tools/test-server.py b/tools/test-server.py
index 16329dc77a4b8d8484676db311e0be7ceaea18a3..ab927de75f4e1e7a252580a9f762e6aad7d4ea38 100755
--- a/tools/test-server.py
+++ b/tools/test-server.py
@@ -78,9 +78,9 @@ def Update():
     import ujson  #@UnusedImport
   except ImportError:
     # Install pip if it doesn't exist.
-    code = subprocess.call("which pip", shell=True)
+    code = subprocess.call("which pip > /dev/null", shell=True)
     if code != 0:
-      apt_get_code = subprocess.call("which apt-get", shell=True)
+      apt_get_code = subprocess.call("which apt-get > /dev/null", shell=True)
       if apt_get_code == 0:
         print("Installing pip...")
         _Cmd("sudo apt-get install python-pip")