Prepare providers release 2026-08-08 (google, cncf.kubernetes) - #71310

Follow-up wave for the two providers pulled from the 2026-08-06 wave.

google was removed on a binding -1 — the provider does not install on
Python 3.14 (tracked in #71268, worked around in #71273, upstream issue
googleapis/python-aiplatform#7057).

cncf.kubernetes is removed here as well: its 10.21.0 candidate declared
version_added: 10.20.0 for the two new concurrent-pod-creation options,
which is wrong — they ship in 10.21.0. Fixed in #71157.

Both were cut as release candidates but never published, so each existing
changelog section is extended rather than superseded and both versions
stay as they are (google 22.3.0, cncf.kubernetes 10.21.0). They will be
cut as 22.3.0rc4 and 10.21.0rc3. source-date-epoch is unchanged for the
same reason.

Changelog entries added for the commits that landed after the 2026-08-06 cut:

• google Workaround bug in google-claude-aiplatform evaluation extra (Python 3… #71273 → Misc (dependency change; the commit subject says
  "google-claude-aiplatform" and "Python 3.15", both of which are wrong, so the
  entry is reworded to what actually shipped)
• google Prepare providers release 2026-08-01 #70932, Update changelog with better wording #71161, Prepare providers release 2026-08-06 #71219 → excluded block (release plumbing, plus a
  wording fix to a historic changelog note)
• cncf.kubernetes Fix version_added for the concurrent pod creation options #71157 → excluded block. The feature whose metadata it
  corrects (Add opt-in concurrent pod creation to KubernetesExecutor #68480) is itself in the unreleased 10.21.0 section, so no user
  ever saw the wrong version_added — this is a within-wave correction, not a
  user-facing change.

No inter-provider >= floor changed, so this does not need the
allow provider dependency bump label.

Was generative AI tooling used to co-author this PR?

• Yes — Claude Code (Opus 5)

Generated-by: Claude Code (Opus 5) following the guidelines