test: removed unused error variable in try catch

In test/parallel/test-fs-access.js

PR-URL: #23553
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

test/parallel/test-fs-access.js

@@ -55,7 +55,7 @@ if (!common.isWindows && process.getuid() === 0) {
   try {
     process.setuid('nobody');
     hasWriteAccessForReadonlyFile = false;
-  } catch (err) {
+  } catch {
   }
 }