Make all RemoteExecutor.Invoke overloads check exit code by default

[elinor-fung]

Currently, only the overloads where the invoked method returns an int or Task<int> check for an expected exit code. This meant that crashes (not caught as a managed exception) would not be detected when those overloads were used. This changes all the overloads to check the exit code by default.

Resolves #5865

cc @stephentoub

[stephentoub]

Thank you. Are you able to validate testing runtime with these changes? I'm wondering if there are any problems silently lurking.

[elinor-fung]

Kicked off a runtime build using the updated RemoteExecutor from this change (assuming I set it up correctly this time): https://dnceng.visualstudio.com/public/_build/results?buildId=1565764

[elinor-fung]

A couple tests were assuming the exit code would not be validated - opened dotnet/runtime#64133.

There is also a consistent crash in System.Tests.TimeZoneInfoTests.NJulianRuleTest that we have been missing - filed dotnet/runtime#64134.

[danmoseley]

Thanks for fixing this @elinor-fung .