doc: fix 404 link of BUILDING.md

PR-URL: #43234
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

BUILDING.md

@@ -608,7 +608,7 @@ packages:
 * [NetWide Assembler](https://chocolatey.org/packages/nasm)
 
 To install Node.js prerequisites using
-[Boxstarter WebLauncher](https://boxstarter.org/WebLauncher), open
+[Boxstarter WebLauncher](https://boxstarter.org/weblauncher), open
 <https://boxstarter.org/package/nr/url?https://github.com/raw/nodejs/node/HEAD/tools/bootstrap/windows_boxstarter>
 with Internet Explorer or Edge browser on the target machine.