Fix 37385 by introducing addition configuration setting

[hun1ahpu]

Fixing the issue #37385
Adding configuration parameter that allows the user to control if s(he) wants to open debug viewlet on every debug session, on the first only or never.

[isidorn]

@hun1ahpu thanks for this PR, I like the work. Here's my feedback, once you adress it we can merge this in:

• I would prefer if this is only a vscode configuration setting, and not a configuration in the launch.json. I know that internalConsoleOptions is present in both configurations and in launch but that is for historic reasons and I am not a fan of that
• I would prefer that the configuration name is debug.openDebug
  That way the name is complementary with debug.openExplorerOnEnd. And the values I would keep as to what you already have.

Thanks a lot

[hun1ahpu]

@isidorn please take a look on the new iteration.
I renamed the setting to openDebugOnStart (similar to openExplorerOnEnd)
I think I've removed it from launch.json setting but I'm not sure. Could you check please?
Thanks

[isidorn]

@hun1ahpu please rename it to exactly openDebug I have discussed the name in great length with a collegue. This is our choice to not have duplication between name and value.
Yes it looks like you have removed it from the launch.json

[hun1ahpu]

@isidorn Done :)

[isidorn]

@hun1ahpu thanks a lot for your PR 🍻. Merging in

[isidorn]

I have cleaned this up a bit via bc04f0c