Use new breakpoint syntax

[octref]

https://code.visualstudio.com/docs/extensions/example-debuggers#_anatomy-of-the-debug-adapter-packagejson
microsoft/vscode#9037 (comment)

[msftclas]

Hi @octref, I'm your friendly neighborhood Microsoft Pull Request Bot (You can call me MSBOT). Thanks for your contribution!

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[roblourens]

Thanks!