doc: removed LTS label from v4 in doc version picker

Fixes: https://github.com/nodejs/node/issues/20903

PR-URL: https://github.com/nodejs/node/pull/20904
Reviewed-By: Weijia Wang <starkwang@126.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

tools/doc/html.js

@@ -345,7 +345,7 @@ function altDocs(filename, docCreated) {
     { num: '7.x' },
     { num: '6.x', lts: true },
     { num: '5.x' },
-    { num: '4.x', lts: true },
+    { num: '4.x' },
     { num: '0.12.x' },
     { num: '0.10.x' }
   ];