Update CFP and add sponsorship link for PyCon US 2026

Author: egeakman

_data/conferences.yml

@@ -795,10 +795,11 @@
 - conference: PyCon US
   year: 2026
   link: https://us.pycon.org/2026/
-  cfp: TBA
+  cfp: 2025-12-19
   place: Long Beach, USA
   start: 2026-05-13
   end: 2026-05-19
+  sponsor: https://us.pycon.org/2026/sponsorship/why-sponsor/
   mastodon: https://fosstodon.org/@pycon
   sub: PY
   location: