Add pip-audit action with version and expiration

This works around #452 (comment).

Not sure if there is any better options.

Signed-off-by: tison <wander4096@gmail.com>

Author: tisonkun

actions.yml

@@ -744,6 +744,10 @@ pre-commit/action:
 PyO3/maturin-action:
   '*':
     keep: true
+pypa/gh-action-pip-audit:
+  1220774d901786e6f652ae159f7b6bc8fea6d266:
+    tag: v1.1.0
+    expires_at: 2026-07-31
 pypa/cibuildwheel:
   63fd63b352a9a8bdcc24791c9dbee952ee9a8abc:
     tag: v3.3.0