Remove outdated summary scripts and markdown files for ArcadeDB and FAISS MSMARCO benchmarks

- Deleted markdown summary files for ArcadeDB search studies (MSMARCO-4M and MSMARCO-8M).
- Removed the summarization scripts for ArcadeDB MSMARCO and search study.
- Deleted the summarization script for FAISS MSMARCO benchmarks.

Author: tae898