Link to legacy docs in readme

Author: mpbw2

README.md

@@ -16,7 +16,7 @@ The Bitwarden mobile application is written in C# using .NET MAUI.
 
 # Build/Run
 
-Please refer to the [Mobile section](https://contributing.bitwarden.com/getting-started/mobile/) of the [Contributing Documentation](https://contributing.bitwarden.com/) for build instructions, recommended tooling, code style tips, and lots of other great information to get you started.
+Please refer to the [Legacy Contributing Documentation](https://github.com/bitwarden/mobile/tree/main/docs/) for build instructions, recommended tooling, code style tips, and lots of other great information to get you started.
 
 # We're Hiring!