PYTHON-3988 Python Test Suite still uses legacy isMaster Command when… (#1395)

Author: NoahStapp

test/__init__.py

@@ -307,7 +307,10 @@ def uri(self):
     @property
     def hello(self):
         if not self._hello:
-            self._hello = self.client.admin.command(HelloCompat.LEGACY_CMD)
+            if self.serverless or self.load_balancer:
+                self._hello = self.client.admin.command(HelloCompat.CMD)
+            else:
+                self._hello = self.client.admin.command(HelloCompat.LEGACY_CMD)
         return self._hello
 
     def _connect(self, host, port, **kwargs):
@@ -317,7 +320,7 @@ def _connect(self, host, port, **kwargs):
         )
         try:
             try:
-                client.admin.command(HelloCompat.LEGACY_CMD)  # Can we connect?
+                client.admin.command("ping")  # Can we connect?
             except pymongo.errors.OperationFailure as exc:
                 # SERVER-32063
                 self.connection_attempts.append(