doc: change links to use HEAD in top level docs

Change the top level docs to use HEAD in links

Signed-off-by: Michael Dawson <mdawson@devrus.com>

PR-URL: #37494
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>

BUILDING.md

@@ -613,7 +613,7 @@ packages:
 
 To install Node.js prerequisites using
 [Boxstarter WebLauncher](https://boxstarter.org/WebLauncher), open
-<https://boxstarter.org/package/nr/url?https://raw.githubusercontent.com/nodejs/node/master/tools/bootstrap/windows_boxstarter>
+<https://boxstarter.org/package/nr/url?https://raw.githubusercontent.com/nodejs/node/HEAD/tools/bootstrap/windows_boxstarter>
 with Internet Explorer or Edge browser on the target machine.
 
 Alternatively, you can use PowerShell. Run those commands from an elevated
@@ -623,7 +623,7 @@ PowerShell terminal:
 Set-ExecutionPolicy Unrestricted -Force
 iex ((New-Object System.Net.WebClient).DownloadString('https://boxstarter.org/bootstrapper.ps1'))
 get-boxstarter -Force
-Install-BoxstarterPackage https://raw.githubusercontent.com/nodejs/node/master/tools/bootstrap/windows_boxstarter -DisableReboots
+Install-BoxstarterPackage https://raw.githubusercontent.com/nodejs/node/HEAD/tools/bootstrap/windows_boxstarter -DisableReboots
 ```
 
 The entire installation using Boxstarter will take up approximately 10 GB of

CODE_OF_CONDUCT.md

@@ -1,4 +1,4 @@
 # Code of Conduct
 
-* [Node.js Code of Conduct](https://github.com/nodejs/admin/blob/master/CODE_OF_CONDUCT.md)
-* [Node.js Moderation Policy](https://github.com/nodejs/admin/blob/master/Moderation-Policy.md)
+* [Node.js Code of Conduct](https://github.com/nodejs/admin/blob/HEAD/CODE_OF_CONDUCT.md)
+* [Node.js Moderation Policy](https://github.com/nodejs/admin/blob/HEAD/Moderation-Policy.md)

CONTRIBUTING.md

@@ -8,7 +8,7 @@
 ## [Code of Conduct](./doc/guides/contributing/code-of-conduct.md)
 
 The Node.js project has a
-[Code of Conduct](https://github.com/nodejs/admin/blob/master/CODE_OF_CONDUCT.md)
+[Code of Conduct](https://github.com/nodejs/admin/blob/HEAD/CODE_OF_CONDUCT.md)
 to which all contributors must adhere.
 
 See [details on our policy on Code of Conduct](./doc/guides/contributing/code-of-conduct.md).

onboarding.md

@@ -114,7 +114,7 @@ The project has two venues for real-time discussion:
     organization (not just Collaborators on Node.js core) have access. Its
     contents should not be shared externally.
   * You can find the full moderation policy
-    [here](https://github.com/nodejs/admin/blob/master/Moderation-Policy.md).
+    [here](https://github.com/nodejs/admin/blob/HEAD/Moderation-Policy.md).
 
 ## Reviewing PRs
 
@@ -247,12 +247,12 @@ needs to be pointed out separately during the onboarding.
   including accommodations, transportation, visa fees, etc. if needed. Check out
   the [summit](https://github.com/nodejs/summit) repository for details.
 
-[Code of Conduct]: https://github.com/nodejs/admin/blob/master/CODE_OF_CONDUCT.md
+[Code of Conduct]: https://github.com/nodejs/admin/blob/HEAD/CODE_OF_CONDUCT.md
 [Landing Pull Requests]: doc/guides/collaborator-guide.md#landing-pull-requests
 [Publicizing or hiding organization membership]: https://help.github.com/articles/publicizing-or-hiding-organization-membership/
 [`author-ready`]: doc/guides/collaborator-guide.md#author-ready-pull-requests
 [`core-validate-commit`]: https://github.com/nodejs/core-validate-commit
-[`git-node`]: https://github.com/nodejs/node-core-utils/blob/master/docs/git-node.md
+[`git-node`]: https://github.com/nodejs/node-core-utils/blob/HEAD/docs/git-node.md
 [`node-core-utils`]: https://github.com/nodejs/node-core-utils
 [set up the credentials]: https://github.com/nodejs/node-core-utils#setting-up-credentials
 [two-factor authentication]: https://help.github.com/articles/securing-your-account-with-two-factor-authentication-2fa/