docs: Remove < 3.11 reference from README (#1502)

Author: jumbosushi

packages/google-cloud-bigquery/README.rst

@@ -52,7 +52,7 @@ dependencies.
 
 Supported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^
-Python >= 3.7, < 3.11
+Python >= 3.7
 
 Unsupported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^