Pull request project-chip#914: update for README links to go to GitHub Pages instead of .md files

Merge in WMN_TOOLS/matter from feature/README-UPDATE-FOR-2.1.0-1.1 to RC_2.1.0-1.1

Squashed commit of the following:

commit 3a39d81c7f745c84b4951a61715c598d29f568f7
Author: Ezra Hale <ezra.hale@silabs.com>
Date:   Fri Jun 23 11:26:49 2023 -0400

    update for README links to go to GitHub Pages instead of .md files

Author: Ezra Hale

README.md

@@ -27,12 +27,12 @@ Device: SiWx917 SoC
 This repo contains documentation, demos, examples and all the code needed for Matter Accessory Device development on both Thread and Wi-Fi. The Thread development use cases differs from Wi-Fi because the Thread protocol requires the use of an Open Thread Border Router (OTBR).  
 
 -   To get started with the Thread demo and development see
-    [Matter Thread](./docs/silabs/thread/DEMO_OVERVIEW.md)
+    [Matter Thread](https://siliconlabs.github.io/matter/2.1.0-1.1/thread/DEMO_OVERVIEW.html)
 -   To get started with the Wi-Fi demo and development see
-    [Matter Wi-Fi](./docs/silabs/wifi/DEMO_OVERVIEW.md)
+    [Matter Wi-Fi](https://siliconlabs.github.io/matter/2.1.0-1.1/wifi/DEMO_OVERVIEW.html)
 
 The full documentation set starts here:
-[Silicon Labs Matter Table of Contents](./docs/silabs/README.md)
+[Silicon Labs Matter GitHub Documentation](https://siliconlabs.github.io/matter/2.1.0-1.1)
 
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