Address swift extension rename

[filiptronicek]

Publishes the extension under the new namespace and also adds a corresponding deprecation entry to the extension control list.

Thanks @NSHaoSong for pointing this out in #721 (comment)!

[filiptronicek]

Error: swiftlang.swift-vscode is dependent on llvm-vs-code-extensions.lldb-dap, which has to be published to Open VSX first

Seems like we'll need to publish the dependency first... let me get back to this

[NSHaoSong]

Error: swiftlang.swift-vscode is dependent on llvm-vs-code-extensions.lldb-dap, which has to be published to Open VSX first

Seems like we'll need to publish the dependency first... let me get back to this

Yes. Looks like we need this extension: https://marketplace.visualstudio.com/items?itemName=llvm-vs-code-extensions.lldb-dap

Just did some digging, the source code of the lldb-dap extension is in llvm's mono repo:
https://github.com/llvm/llvm-project/tree/main/lldb/tools/lldb-dap

And there's a separate repo (https://github.com/llvm/vscode-lldb) contains only the VSCode extension srcs, and has a GitHub workflow to publish to VSCode Marketplace:
https://github.com/llvm/vscode-lldb/blob/main/.github/workflows/auto_publish.yml