feat: add Arrrow FlightSQL documentation

modules/arrow-flightsql/index.md

@@ -0,0 +1,19 @@
+---
+title: Apache Arrow FlightSQL server
+categories:
+  - other
+docs:
+  - id: rust
+    url: https://docs.rs/testcontainers-modules/latest/testcontainers_modules/index.html
+    maintainer: community
+    example: |
+      ```rust
+      testcontainers_modules::arrow_flightsql::ArrowFlightSQL::default().start()
+      ```
+    installation: |
+      ```bash
+      cargo add -F arrow_flightsql --dev testcontainers-modules
+      ```
+description: |
+  Apache Arrow FlightSQL is a high-performance RPC service that exposes SQL query execution and result streaming over Apache Arrow to clients, backed by an existing database or query engine.
+---