test: fix common.enoughTestMem

A typo introduced in 1ddcb6d2a70 causes common.enoughTestMem to always
be false, resulting in a lot of tests being skipped. Fix the typo.

PR-URL: https://github.com/nodejs/node/pull/31035
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: David Carlier <devnexen@gmail.com>

test/common/index.js

@@ -788,7 +788,7 @@ module.exports = {
     return Array.isArray(cpus) && (cpus.length > 1 || cpus[0].speed > 999);
   },
 
-  get enoughTestMeme() {
+  get enoughTestMem() {
     return require('os').totalmem() > 0x70000000; /* 1.75 Gb */
   },