chore: limit update to 0.98.0 NUX to < 0.98.0 ver (openai#10787)

seems like footgun if we forget to remove before releasing 0.99.0,
limited announcement to versions < 0.98.0

Author: sayan-oai

announcement_tip.toml

@@ -20,3 +20,4 @@ to_date = "2026-05-10"
 content = "**BREAKING NEWS**: `gpt-5.3-codex` is out! Upgrade to `0.98.0` to try it."
 from_date = "2026-02-01"
 to_date = "2026-02-15"
+version_regex = "^0\\.(?:[0-9]|[1-8][0-9]|9[0-7])\\."