Add option to open server in VSCode's built in browser

[iqfareez]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report  <!-- Please search GitHub for a similar issue or PR before submitting -->
[x] Feature request
[ ] Documentation issue or request
[ ] Other: <!-- Please describe: -->

Current behavior

When starting server, it will open my default browser.

Expected behavior

I'm aware of this setting liveServer.settings.CustomBrowser where I can change the behavior. However, I would like to see it open in built in Vscode Simple Browser so I can work with the file side by side.

Current workaround was copy the localhost url in the opened browser, then open Simple Browser: Show to paste the link.

Environment

Browser:

- [ ] Chrome (desktop) version XX
- [ ] Firefox version XX
- [ ] Safari (desktop) version XX
- [ ] IE version XX
- [ ] Edge version XX

For Tooling issues:

- Live Server: v5.7.5
- Platform:  Windows 11
- Visual Studio Code: 1.68.1