Add best practices to reduce disk space in storage section

Some of our users could find the tips in our [indexing performance](https://www.meilisearch.com/docs/learn/advanced/indexing) section helpful for optimizing Meilisearch's storage utilization.
See this user's [comment](https://github.com/meilisearch/meilisearch/issues/4211#issuecomment-1821541945)