Drop deprecated and incorrect result files

- starrocks/results/{20220715,20220925}/*.untuned.json — old untuned
  variant from when both tuned and untuned runs were captured
  separately. The canonical c6a.4xlarge.json / c6a.metal.json next
  to them already record an untuned run (tuned="no") with the
  modern schema.
- timescaledb/results/20220701/c6a.4xlarge.compression.json — old
  compression-on variant; the canonical c6a.4xlarge.json carries
  the standard TimescaleDB run for that date.
- trino{,-partitioned}/results/202605{06,07}/c8g*.json — c8g runs
  removed entirely (per maintainer instruction).
- umbra/results/20251026/c6a.{2xlarge,xlarge}.json — incorrect
  results, removed entirely.
- arc/results/2025*/m3_max*.json — m3_max runs removed entirely.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: alexey-milovidov