Log standard out on passing tests

[pblasucci]

This PR slightly modifies the code in TestExplorer.fs, such that if a TRX file contains output, it is emitted for passing tests. This is similar to the behavior of JetBrains Rider. Further, it facilitates having meaningful output when, eg, using FsCheck.

For example, the following test:

[<Property>]
let ``test some stuff`` (PositiveInt value) =
    (0 < value) |> Prop.collect value

will print output like the following:

Happy to hear feedback on this (esp. from @farlee2121 and @TheAngryByrd). Thanks!

[farlee2121]

I think that's a great feature add!

I left one comment on the intended structure of the TRX types.
Someone else might have thoughts about the global.json and package.json changes.

Some related work: I'm working on moving us away from TRX parsing to using the VsTest platform and eventually the Microsoft Testing Platform.

I did some poking around to make sure we'll be able to support StdOut once the move from TRX to VsTest or MTP is done.
MTP clearly supports standard out per test, but I haven't been able to track down how it'd work with VsTest. It's got to be possible if the info is available in the trx file.

[pblasucci]

I think that's a great feature add!

Thanks! Happy to help. I've change the code per your suggestions.

Someone else might have thoughts about the global.json and package.json changes.

For context, I needed the change to global.json in order to get things to build (without my having to go hunt down a specific older version of the SDK). However, I have no idea, really, about the packages.json file -- it's just something the tooling automatically changed for me (I really do not understand all the Fable / JS / TS wizardry).

[TheAngryByrd]

global.json

It's such a pain, it's always wrong 😂 . Don't worry about it.

package.json

looks to be pinning a version of yarn, which is probably fine.

[TheAngryByrd]

Gonna approve it. @pblasucci have any other changes before I merge and ship it?

[pblasucci]

Nope. I'm all set @TheAngryByrd. If it's good for you and @farlee2121, then it's good for me. 👍