chore: update electron to ^28.2.8

[sdirix]

What it does

Updates Electron dependency to ^28.2.8, the same version as used in VS Code.

Note: It's not 100% the same version. VS Code is fixed on 28.2.8 while ^28.2.8 currently resolves to 28.2.10

How to test

Build and run the Electron example application

Follow-ups

Downstream projects like the Theia IDE also need to update then.

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

Closes #12855

[sdirix]

The license check fails with

ERROR: Found results that aren't part of the baseline!
X npm/npmjs/-/electron-mocha/12.3.0, 

However npm lists the license as MIT, see here.
Same in the repository, see here.

We used electron-mocha before too, this PR just updates it by one major version. How can we resolve this?

[msujew]

@sdirix I've instructed clearlydefined.io to harvest the version of that library. It's the data source of the dash license check tool. It's now correctly recognized.

[sdirix]

@msujew Do you want to review/merge this PR?

[msujew]

@sdirix I can take a look at this tomorrow 👍

[msujew]

Looks good to me. Even the more complex features (i.e. secondary window support) worked as expected for me. However, I could only test on Windows, so anyone with a Mac/Linux PC looking at this would be appreciated.

[JonasHelming]

@sdirix Could you rebase so I can merge this?

[sdirix]

@sdirix Could you rebase so I can merge this?

@JonasHelming Done