gh-148788: Update Emscripten example post move to Platforms dir (#148761)

Update Emscripten example post move to Platforms dir.

Author: StanFromIreland

Platforms/emscripten/web_example/index.html

@@ -663,9 +663,9 @@ <h1>Simple REPL for Python WASM</h1>
                 The simple REPL provides a limited Python experience in the
                 browser.
                 <a
-                    href="https://github.com/python/cpython/blob/main/Tools/wasm/README.md"
+                    href="https://github.com/python/cpython/blob/main/Platforms/emscripten/README.md"
                 >
-                    Tools/wasm/README.md
+                    Platforms/emscripten/README.md
                 </a>
                 contains a list of known limitations and issues. Networking,
                 subprocesses, and threading are not available.
@@ -679,9 +679,9 @@ <h1>Simple REPL for Python WASM</h1>
                 your browser instead of using <code>server.py</code> as
                 described in
                 <a
-                    href="https://github.com/python/cpython/blob/main/Tools/wasm/README.md#the-web-example"
+                    href="https://github.com/python/cpython/blob/main/Platforms/emscripten/README.md#the-web-example"
                 >
-                    Tools/wasm/README.md
+                    Platforms/emscripten/README.md
                 </a>.
             </p>
             <p>