[XamariniOSV2] Delete vsts-task-lib from package-lock.json

[alexander-smolyakov]

Task name: XamariniOSV2

Description:
Since the related task migrated to azure-pipelines-task-lib there is no need to keep vsts-task-lib in lock-file.

Documentation changes required: No

Added unit tests: No

Attached related issue:

• https://github.com/microsoft/build-task-team/issues/144

Checklist:

• Task version was bumped - please check instruction how to do it
• Checked that applied changes work as expected

Note:
I increased timeouts on some unit tests. Since there was an issue related to macOS checks and unit tests fails with this error:
Error: timeout of *ms exceeded. Ensure the done() callback is being called in this test.