test: fix node 6 tests by pinning to sax 1.4.1 in old node versions (#4925)

Fixes errors like
https://github.com/dequelabs/axe-core/actions/runs/19046409251/job/54395759156

Author: dbjorge

test/node/node.js

@@ -33,29 +33,28 @@ initJsdom(function (err, window) {
  */
 function initJsdom(callback) {
   try {
-    var nodeToJsdomMatrix = {
-      4: '9.12.0', // last jsdom version that supported this node version
-      6: '11.12.0',
-      8: '15.2.1',
-      10: '16.7.0',
-      12: '19.0.0',
-      14: '21.1.2',
-      16: '22.1.0',
-      18: '26.1.0'
+    var nodeToDeps = {
+      4: ['jsdom@9.12.0', '[email protected]'], // last jsdom version that supported this node version
+      6: ['jsdom@11.12.0', '[email protected]'],
+      8: ['jsdom@15.2.1'],
+      10: ['jsdom@16.7.0'],
+      12: ['jsdom@19.0.0'],
+      14: ['jsdom@21.1.2'],
+      16: ['jsdom@22.1.0'],
+      18: ['jsdom@26.1.0']
     };
 
     var majorNodeVersion = process.versions.node.split('.')[0];
-    var jsdomVersion = nodeToJsdomMatrix[majorNodeVersion] || 'latest';
-
     console.log('node version detected as: v' + majorNodeVersion);
-    console.log('installing jsdom@' + jsdomVersion);
-    var child = spawn(
-      'npm',
-      ['install', 'jsdom@' + jsdomVersion, '--no-save'],
-      {
-        cwd: __dirname
-      }
-    );
+
+    var deps = nodeToDeps[majorNodeVersion] || ['jsdom@latest'];
+    var nodeInstallArgs = ['install', '--no-save'];
+    for (var dep of deps) {
+      console.log('installing ' + dep);
+      nodeInstallArgs.push(dep);
+    }
+
+    var child = spawn('npm', nodeInstallArgs, { cwd: __dirname });
     child.stdout.setEncoding('utf8');
     child.stderr.setEncoding('utf8');
     child.stdout.on('data', function (data) {