doc: fixup after rename of primary nodejs branch

Signed-off-by: Michael Dawson <[email protected]>

PR-URL: #43453
Reviewed-By: LiviaMedeiros <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>
Reviewed-By: Tobias Nießen <[email protected]>

Author: mhdawson

doc/contributing/security-model-strategy.md

@@ -2,7 +2,7 @@
 
 A clear security model, with features like permissions and policy enforcement,
 is a
-[top technical priority](https://github.com/nodejs/node/blob/master/doc/contributing/technical-priorities.md#permissionspoliciessecurity-model)
+[top technical priority](https://github.com/nodejs/node/blob/HEAD/doc/contributing/technical-priorities.md#permissionspoliciessecurity-model)
 of Node.js.
 
 ## High-level approach