test: use fipsMode in test-crypto-fips

This commit updates test/parallel/test-crypto-fips.js to use fipsMode
instead of process.config.variables.openssl_fips.

The motivation for this is that since the addition of the
--openssl-is-fips configuration flag, it is possible to dynamically
link with a FIPS compliant OpenSSL library. Using fipsMode allows for
determining if there is FIPS support when statically or dynamically
linking against a FIPS compatible OpenSSL library.

PR-URL: #25563
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/parallel/test-crypto-fips.js

@@ -1,3 +1,4 @@
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 if (!common.hasCrypto)
@@ -7,6 +8,8 @@ const assert = require('assert');
 const spawnSync = require('child_process').spawnSync;
 const path = require('path');
 const fixtures = require('../common/fixtures');
+const { internalBinding } = require('internal/test/binding');
+const { fipsMode } = internalBinding('config');
 
 const FIPS_ENABLED = 1;
 const FIPS_DISABLED = 0;
@@ -24,7 +27,7 @@ const CNF_FIPS_OFF = fixtures.path('openssl_fips_disabled.cnf');
 let num_children_ok = 0;
 
 function compiledWithFips() {
-  return process.config.variables.openssl_fips ? true : false;
+  return fipsMode ? true : false;
 }
 
 function sharedOpenSSL() {