[SPARK-52048] Add Swift Web Server example repository link

### What changes were proposed in this pull request?

This PR aims to add `Swift Web Server` example repository link.

- https://github.com/dongjoon-hyun/spark-connect-swift-web

```
$ curl http://127.0.0.1:8080/hello
Connected to Apache Spark 4.0.0 Server%
```

### Why are the changes needed?

To provide more examples.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Manual review.

### Was this patch authored or co-authored using generative AI tooling?

No.

Closes #116 from dongjoon-hyun/SPARK-52048.

Authored-by: Dongjoon Hyun <[email protected]>
Signed-off-by: Dongjoon Hyun <[email protected]>

Author: dongjoon-hyun

README.md

@@ -108,9 +108,10 @@ SELECT * FROM t
 +----+
 ```
 
-You can find this example in the following repository.
+You can find this command line example and additional `Swift Web Server` example in the following repositories.
 
 - <https://github.com/dongjoon-hyun/spark-connect-swift-app>
+- <https://github.com/dongjoon-hyun/spark-connect-swift-web>
 
 ## How to use `Spark SQL REPL` via `Spark Connect for Swift`