Fix doc links for making requests directly to WSGI/ASGI apps (#3186)

Author: kiendang

README.md

@@ -66,7 +66,7 @@ HTTPX builds on the well-established usability of `requests`, and gives you:
 * An integrated command-line client.
 * HTTP/1.1 [and HTTP/2 support](https://www.python-httpx.org/http2/).
 * Standard synchronous interface, but with [async support if you need it](https://www.python-httpx.org/async/).
-* Ability to make requests directly to [WSGI applications](https://www.python-httpx.org/advanced/#calling-into-python-web-apps) or [ASGI applications](https://www.python-httpx.org/async/#calling-into-python-web-apps).
+* Ability to make requests directly to [WSGI applications](https://www.python-httpx.org/advanced/transports/#wsgi-transport) or [ASGI applications](https://www.python-httpx.org/advanced/transports/#asgi-transport).
 * Strict timeouts everywhere.
 * Fully type annotated.
 * 100% test coverage.

docs/index.md

@@ -68,7 +68,7 @@ HTTPX builds on the well-established usability of `requests`, and gives you:
 * A broadly [requests-compatible API](compatibility.md).
 * Standard synchronous interface, but with [async support if you need it](async.md).
 * HTTP/1.1 [and HTTP/2 support](http2.md).
-* Ability to make requests directly to [WSGI applications](async.md#calling-into-python-web-apps) or [ASGI applications](async.md#calling-into-python-web-apps).
+* Ability to make requests directly to [WSGI applications](advanced/transports.md#wsgi-transport) or [ASGI applications](advanced/transports.md#asgi-transport).
 * Strict timeouts everywhere.
 * Fully type annotated.
 * 100% test coverage.