Improve synonyms storage

✨ Enhancement

• Improve the synonyms storage by @Kerollmops in #6466
  We improve synonyms' performance by changing how we store and retrieve them during query processing. Users may have experienced performance issues when the number of synonyms in an index was high, resulting in a significant impact on search performance. The Meilisearch support team advised moving the settings and synonyms-as-keywords to the dedicated documents. This is no longer an issue; synonyms are loaded lazily, only when a word matches a synonym. You can see performance improvements of up to 13x, depending on the number of synonyms.

🔩 Miscellaneous

• Fix the workflow after broken ranking scores by @Kerollmops in #6470
• Make OpenAPI rule less strict for routes returning 202 by @curquiza in #6488