Add the release note for Python client 3.8.0 (#1027)

Author: BewareMyPower

data/release-python.js

@@ -0,0 +1,18 @@
+---
+id: client-python-3.8.0
+title: Client Python 3.8.0
+sidebar_label: Client Python 3.8.0
+---
+
+## What's Changed
+* Bumped version to 3.8.0a1 by @shibd in https://github.com/apache/pulsar-client-python/pull/255
+* fix: added schema to messages in batch_receive method by @danilopezma in https://github.com/apache/pulsar-client-python/pull/215
+* Support deserializing a message id from bytes and topic by @BewareMyPower in https://github.com/apache/pulsar-client-python/pull/259
+* Remove version upper bound for protobuf dependency by @merlimat in https://github.com/apache/pulsar-client-python/pull/260
+* Bump C++ client to 3.7.2 by @BewareMyPower in https://github.com/apache/pulsar-client-python/pull/264
+* Support message router by @BewareMyPower in https://github.com/apache/pulsar-client-python/pull/265
+
+## New Contributors
+* @danilopezma made their first contribution in https://github.com/apache/pulsar-client-python/pull/215
+
+**Full Changelog**: https://github.com/apache/pulsar-client-python/compare/v3.7.0...v3.8.0