downloads: upgrade CPython 3.9.14 -> 3.9.15

Author: indygreg

pythonbuild/downloads.py

@@ -44,10 +44,10 @@
         "python_tag": "cp38",
     },
     "cpython-3.9": {
-        "url": "https://www.python.org/ftp/python/3.9.14/Python-3.9.14.tar.xz",
-        "size": 19750176,
-        "sha256": "651304d216c8203fe0adf1a80af472d8e92c3b0e0a7892222ae4d9f3ae4debcf",
-        "version": "3.9.14",
+        "url": "https://www.python.org/ftp/python/3.9.15/Python-3.9.15.tar.xz",
+        "size": 19712208,
+        "sha256": "12daff6809528d9f6154216950423c9e30f0e47336cb57c6aa0b4387dd5eb4b2",
+        "version": "3.9.15",
         "licenses": ["Python-2.0", "CNRI-Python"],
         "license_file": "LICENSE.cpython.txt",
         "python_tag": "cp39",