source-mixpanel-native: increase funnels date window size

This implements the fix made to `annotations` in
8284cbc to the `funnels` stream. The
connector has to send at least one API request for each funnel, and for
users with hundreds of funnels, this will a minimum take multiple hours.
If the connector uses a small date window size & makes more than a
single request per funnel, then it's possible for `funnels` to never
complete in 24 hours.

Since each funnel typically only has KB of data, we can force `funnels`
to make a single request per funnel by using a very large date window size.

source-mixpanel-native/source_mixpanel_native/streams/funnels.py

@@ -43,6 +43,23 @@ def state_checkpoint_interval(self) -> int:
         # we'll have to emit state every 15 records
         return 1000
 
+    def __init__(
+        self,
+        date_window_size: int = 30,
+        **kwargs,
+    ):
+        # This stream checks from the start_date to the end_date for each funnel. Typically,
+        # there's KB of data between the start_date & end_date for each funnel, and using
+        # small date windows causes the connector to make multiple requests for each funnel.
+        # Since we should be able to fetch all data for a funnel in a single request,
+        # we use an extremely large data window to force the connector to make a single request
+        # for all of a funnel's records between the start & end dates.
+
+        super().__init__(
+            date_window_size = 100_000,
+            **kwargs,
+        )
+
     def path(self, **kwargs) -> str:
         return "funnels"