PYTHON-2808 Use Invoke-WebRequest instead certifi to workaround FLE test issue (#714)

(cherry picked from commit 6913738)

Author: ShaneHarvey

.evergreen/run-tests.sh

@@ -129,6 +129,8 @@ if [ -n "$TEST_ENCRYPTION" ]; then
 
     if [ "Windows_NT" = "$OS" ]; then # Magic variable in cygwin
         $PYTHON -m pip install -U setuptools
+        # PYTHON-2808 Ensure this machine has the CA cert for google KMS.
+        powershell.exe "Invoke-WebRequest -URI https://oauth2.googleapis.com/" > /dev/null || true
     fi
 
     if [ -z "$LIBMONGOCRYPT_URL" ]; then
@@ -171,10 +173,6 @@ if [ -n "$TEST_ENCRYPTION" ]; then
     . $DRIVERS_TOOLS/.evergreen/csfle/set-temp-creds.sh
 
     # Start the mock KMS servers.
-    if [ "$OS" = "Windows_NT" ]; then
-        # Remove after BUILD-13574.
-        python -m pip install certifi
-    fi
     # The mock KMS server requires Python >=3.5 with boto3.
     IS_PRE_35=$(python -c "import sys; sys.stdout.write('1' if sys.version_info < (3, 5) else '0')")
     if [ $IS_PRE_35 = "1" ]; then

test/test_encryption.py

@@ -56,8 +56,7 @@
 from test import (unittest,
                   client_context,
                   IntegrationTest,
-                  PyMongoTestCase,
-                  SystemCertsPatcher)
+                  PyMongoTestCase)
 from test.utils import (TestCreator,
                         camel_to_snake_args,
                         OvertCommandListener,
@@ -67,26 +66,6 @@
                         wait_until)
 from test.utils_spec_runner import SpecRunner
 
-try:
-    import certifi
-    HAVE_CERTIFI = True
-except ImportError:
-    HAVE_CERTIFI = False
-
-patcher = None
-
-
-def setUpModule():
-    if sys.platform == 'win32' and HAVE_CERTIFI:
-        # Remove after BUILD-13574.
-        global patcher
-        patcher = SystemCertsPatcher(certifi.where())
-
-
-def tearDownModule():
-    if patcher:
-        patcher.disable()
-
 
 def get_client_opts(client):
     return client._MongoClient__options