[pytz] Bump to 2026.5 (#16476)

Author: github-actions[bot]

stubs/pytz/METADATA.toml

@@ -1,3 +1,3 @@
 # This is a mirror of https://git.launchpad.net/pytz/tree, see https://pythonhosted.org/pytz/#latest-versions
-version = "2026.4"
+version = "2026.5"
 upstream-repository = "https://github.com/stub42/pytz"