add vscode settings to format files on save (#6579)

.vscode/settings.json

@@ -0,0 +1,8 @@
+{
+    "editor.formatOnSave": true,
+    "files.insertFinalNewline": true,
+    "files.trimFinalNewlines": true,
+    "editor.detectIndentation": false,
+    "editor.tabSize": 4,
+    "editor.insertSpaces": true,
+}