chore: Change case for readme.rst

Author: yevgenypats

setup.py

@@ -19,7 +19,7 @@
 
 package_root = os.path.abspath(os.path.dirname(__file__))
 
-readme_filename = os.path.join(package_root, "README.rst")
+readme_filename = os.path.join(package_root, "readme.rst")
 with io.open(readme_filename, encoding="utf-8") as readme_file:
     readme = readme_file.read()