fix(bindings/python): Make sure read until EOF (#4995)

* Fix #4990 guarantees read until EOF

* Address code review feedback for solving issue #4990

* Fix: Ensure full content is read before performing assertions

This commit addresses the issue raised in the pull request #4989, where the `read()` operation did not always return the expected content length.

Changes include:
- Implementing a loop to gather all content chunks until EOF.
- Performing the assertion after the entire content has been read.

This ensures that the test passes stably by correctly handling cases where `read()` may not return the full content in one go.

* address pr code review comment

* addressed pr code review by deleting requested code in my pr

bindings/python/tests/test_read.py

@@ -54,7 +54,14 @@ def test_sync_reader(service_name, operator, async_operator):
         assert read_content == content
 
     with operator.open(filename, "rb") as reader:
-        read_content = reader.read(size + 1)
+        read_content = bytearray()
+        while True:
+            chunk = reader.read(size + 1)
+            if not chunk:
+                break
+            read_content.extend(chunk)
+
+        read_content = bytes(read_content)
         assert read_content is not None
         assert read_content == content