downloads: upgrade CPython 3.10 to 3.10.0

3.10 was released yesterday. Let's use it.

Author: indygreg

pythonbuild/downloads.py

@@ -71,10 +71,10 @@
         "python_tag": "cp39",
     },
     "cpython-3.10": {
-        "url": "https://www.python.org/ftp/python/3.10.0/Python-3.10.0rc2.tar.xz",
-        "size": 18737220,
-        "sha256": "e75b56088548b7b9ad1f2571e6f5a2315e4808cb6b5fbe8288502afc802b2f24",
-        "version": "3.10.0rc2",
+        "url": "https://www.python.org/ftp/python/3.10.0/Python-3.10.0.tar.xz",
+        "size": 18726176,
+        "sha256": "5a99f8e7a6a11a7b98b4e75e0d1303d3832cada5534068f69c7b6222a7b1b002",
+        "version": "3.10.0",
         "licenses": ["Python-2.0", "CNRI-Python"],
         "license_file": "LICENSE.cpython.txt",
         "python_tag": "cp310",