doc: fix cjs example code for process.arch

PR-URL: #41593
Reviewed-By: Mestery <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Qingyu Deng <[email protected]>
Reviewed-By: Mohammed Keyvanzadeh <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Tobias Nießen <[email protected]>

doc/api/process.md

@@ -875,7 +875,7 @@ 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`