Update _reject_ongoing_promises with Promise.allSettled()

[KSDaemon]

Description, Motivation and Context

Trying to fix unhandled promises during disconnection. Updated _reject_ongoing_promises() with Promise.allSettled() so all promises should be done (fulfilled or rejected).

This might fix #276

What kind of change does this PR introduce?

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactoring (no new functionality, only code improvements)

Checklist:

• My code follows the code style of this project.
• I have added tests to cover my changes.
• Overall test coverage is not decreased.
• All new and existing tests passed.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.