Mention Graal.JS as needed when GraalVM is runtime JDK behind proxy (#5785)

* Remove JDK8 as minimum for build of VSNetBeans.

* Remove mention of JDK8 as lowest

* Install Graal.JS when running on GraalVM
diff --git a/java/java.lsp.server/vscode/README.md b/java/java.lsp.server/vscode/README.md
index 8926dca..1fd1bee 100644
--- a/java/java.lsp.server/vscode/README.md
+++ b/java/java.lsp.server/vscode/README.md
@@ -35,6 +35,8 @@
     subprojects etc.
 4. Or simply create a new Java class file with `public static void main(String[] args)` method in opened folder and start coding, compiling, debugging. Works on JDK 8 and newer.
 
+## Proxy Issues
+When running this extension on GraalVM, as its runtime JDK, behind proxy it requires GraalVM JavaScript (Graal.JS) component installed to perform automatic proxy resolution. Either install Graal.JS using GraalVM VSCode extension available on Marketplace or invoke `gu install js` for GraalVM used by VSCode.
 
 ## Supported Actions
 * __Java: New Project...__ allows creation of new Maven or Gradle project