[Tests]: Some tests are failing when Windows is set to use codepage 65001

### Issue Description

At least `ToolTask_Tests.ToolTaskCanUseUnicode` and `EncodingUtilities_Tests.CanEncode` tests are failing when UTF-8 support is enabled. I would proactively disable these tests in this scenario, but I'm not familiar with the background (or reason) for these encoding tests :)

### Steps to Reproduce

Go to: `Control panel > Region > Administrative > Change system locale` and enable `Use Unicode UTF-8 for worldwide language support`

Run mentioned tests

### Expected Behavior

Tests should pass

### Actual Behavior

Tests are failing