runner: initialize COM security, so toast notifications work in elevated context from non-admin account

[yuyoyuppe]

Summary of the Pull Request

To avoid 0x80070005 (Access denied) error in wpnapps.dll when trying to show toast in the context described in the title, it's crucial to add L"(A;;0x7;;;IU)" permission to the COM security descriptor and initialize COM with it.

PR Checklist

• Applies to common: toast notifications doesn't work on running as elevated from non-admin account #5313
• CLA signed. If not, go over here and sign the CLA
• Tests added/passed
• I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx

Validation Steps Performed

• launched PowerToys from an elevated cmd shell from non-admin account

[yuyoyuppe]

I suggest we merge it once the 0.20.x is released to avoid regressions, since this PR could have unpredicted side-effects.

[enricogior]

Tested, it worked as expected.