plugin: align provideTasks with vscode

[vince-fugnitto]

What it does

Fixes: #8662.

The pull-request updates $provideTasks (ext-side) with the expectations of vscode and uses the CancellationToken.None when calling provideTasks from the task provider adapter.

• vscode $provideTasks
• vscode $provideTasks CancellationToken.None
• protocol

How to test

1. update vscode.typescript-language-features plugin to 1.50.0:
   • https://open-vsx.org/extension/vscode/typescript/1.50.0
2. start the application with a typescript project (ex: theia).
3. open the npm scripts view in the explorer, the view should be populated.

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

Additional Information

Prerequisite for #10049.

Signed-off-by: vince-fugnitto vincent.fugnitto@ericsson.com

[tsmaeder]

I can confirm "Run Task..." works with the 1.50.0-level built-ins. In the long run, we should think about being able to really cancel the call, but let's cross that bridge when we get to it.