downloads: upgrade Python 3.8 to 3.8.6

It was released a few days ago. Let's build the latest/greatest Python.

Author: indygreg

pythonbuild/downloads.py

@@ -62,10 +62,10 @@
         "python_tag": "cp37",
     },
     "cpython-3.8": {
-        "url": "https://www.python.org/ftp/python/3.8.5/Python-3.8.5.tar.xz",
-        "size": 18019640,
-        "sha256": "e3003ed57db17e617acb382b0cade29a248c6026b1bd8aad1f976e9af66a83b0",
-        "version": "3.8.5",
+        "url": "https://www.python.org/ftp/python/3.8.6/Python-3.8.6.tar.xz",
+        "size": 18233864,
+        "sha256": "a9e0b79d27aa056eb9cce8d63a427b5f9bab1465dee3f942dcfdb25a82f4ab8a",
+        "version": "3.8.6",
         "licenses": ["Python-2.0", "CNRI-Python"],
         "license_file": "LICENSE.cpython.txt",
         "python_tag": "cp38",