doc: fix cjs example code for process.arch

PR-URL: #41593
Reviewed-By: Mestery <mestery@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Qingyu Deng <i@ayase-lab.com>
Reviewed-By: Mohammed Keyvanzadeh <mohammadkeyvanzade94@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

doc/api/process.md

@@ -873,7 +873,7 @@ console.log(`This processor architecture is ${arch}`);
 ```cjs
 const { arch } = require('process');
 
-console.log(`This processor architecture is ${process.arch}`);
+console.log(`This processor architecture is ${arch}`);
 ```
 
 ## `process.argv`