option to configure experiments in the workspace `settings.json`

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currently, the following settings can only be configured in a user settings.json:

• python.experiments.enabled
• python.experiments.optInto
• python.experiments.optOutFrom

it would be nice if these could be configured in a workspace settings.json as well.

my use case is that my project relies on the new pytest rewrite because i have a hook function that relies on the vscode_pytest plugin (see my comment on #20086 (comment))

while in this case, the experiment is supposed to be enabled by for all users (though that doesn't seem to be the case for some reason), there are still other potential future experiments that users may want to enable or disable for everyone working on their project.