src,test: further cleanup references to osx

PR-URL: https://github.com/nodejs/node/pull/53820
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>

node.gypi

@@ -225,7 +225,7 @@
     }],
 
     [ 'OS=="mac"', {
-      # linking Corefoundation is needed since certain OSX debugging tools
+      # linking Corefoundation is needed since certain macOS debugging tools
       # like Instruments require it for some features
       'libraries': [ '-framework CoreFoundation' ],
       'defines!': [