fix: listen bucket event response should use response.readline() (#1195)

using response.stream() doesn't work with nginx due to unknown
reasons, mostly perhaps how nginx writes the body of the
response. Instead use response.readline() instead allows for
reading the right amount of content() needed for events.

Author: harshavardhana

minio/datatypes.py

@@ -811,7 +811,6 @@ class EventIterable:
     def __init__(self, func):
         self._func = func
         self._response = None
-        self._stream = None
 
     def _close_response(self):
         """Close response."""
@@ -826,7 +825,7 @@ def __iter__(self):
     def _get_records(self):
         """Get event records from response stream."""
         try:
-            line = self._stream.__next__().strip()
+            line = self._response.readline().strip()
             if not line:
                 return None
             if hasattr(line, 'decode'):
@@ -843,7 +842,6 @@ def __next__(self):
         while not records:
             if not self._response:
                 self._response = self._func()
-                self._stream = self._response.stream()
             records = self._get_records()
         return records