lib: add missing env vars to --help

PR-URL: #43492
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>
Reviewed-By: Feng Yu <F3n67u@outlook.com>

Author: cola119

lib/internal/main/print_help.js

@@ -55,10 +55,15 @@ const envVars = new SafeMap(ArrayPrototypeConcat([
 'of stderr'}],
 ['NODE_REPL_HISTORY',{helpText: 'path to the persistent REPL '+
 'history file'}],
+['NODE_REPL_EXTERNAL_MODULE',{helpText: 'path to a Node.js module '+
+'which will be loaded in place of the built-in REPL'}],
+['NODE_SKIP_PLATFORM_CHECK',{helpText: 'set to 1 to skip '+
+'the check for a supported platform during Node.js startup'}],
 ['NODE_TLS_REJECT_UNAUTHORIZED',{helpText: 'set to 0 to disable TLS '+
 'certificate validation'}],
 ['NODE_V8_COVERAGE',{helpText: 'directory to output v8 coverage JSON '+
 'to'}],
+['TZ',{helpText: 'specify the timezone configuration'}],
 ['UV_THREADPOOL_SIZE',{helpText: 'sets the number of threads used in '+
 'libuv\'s threadpool'}],
 ],hasIntl ? [