chore: Provide a working Windows installation link

Author: manyinsects

README.md

@@ -42,7 +42,7 @@ Set-ExecutionPolicy RemoteSigned
 Then, you can run:
 
 ```ps
-Start-BitsTransfer -Source https://git.io/install-rustlings-win -Destination $env:TMP/install_rustlings.ps1; Unblock-File $env:TMP/install_rustlings.ps1; Invoke-Expression $env:TMP/install_rustlings.ps1
+Start-BitsTransfer -Source https://git.io/JTL5v -Destination $env:TMP/install_rustlings.ps1; Unblock-File $env:TMP/install_rustlings.ps1; Invoke-Expression $env:TMP/install_rustlings.ps1
 ```
 
 To install Rustlings. Same as on MacOS/Linux, you will have access to the `rustlings` command after it.