tools: upgrade Windows digital signature to SHA256

signtool still defaults to SHA1, which is vulnerable to certain
collisions. This switches to SHA256, which is stronger and which also
matches the hash function used by the signing certificate.

Technically, `/fd certHash` would be a better choice, but I don't know
if it is widely supported.

PR-URL: #47206
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

tools/sign.bat

@@ -3,7 +3,7 @@
 set timeservers=(http://timestamp.globalsign.com/scripts/timestamp.dll http://timestamp.comodoca.com/authenticode http://timestamp.verisign.com/scripts/timestamp.dll http://tsa.starfieldtech.com)
 
 for %%s in %timeservers% do (
-    signtool sign /a /d "Node.js" /du "https://nodejs.org" /t %%s %1
+    signtool sign /a /d "Node.js" /du "https://nodejs.org" /fd SHA256 /t %%s %1
     if not ERRORLEVEL 1 (
         echo Successfully signed %1 using timeserver %%s
         exit /b 0