Upgrade pyright (#3063)

* upgrade pyright versoin

* add changelog

* Downgrade pyright version in dev requirements

Author: msyyc

.chronus/changes/upgrade-pyright-2025-2-27-11-12-41.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@azure-tools/typespec-python"
+---
+
+Upgrade pyright version

packages/typespec-python/dev_requirements.txt

@@ -1,5 +1,5 @@
 # shall keep aligned with dev_requirements.txt of @typspec/http-client-python
-pyright==1.1.389
+pyright==1.1.391
 pylint==3.2.7
 tox==4.23.2
 mypy==1.13.0
@@ -12,4 +12,4 @@ ptvsd==4.3.2
 types-PyYAML==6.0.12.20241230
 
 # additional dependency needed for development
-setuptools
+setuptools