7.9.0

Updates FSAC to 0.62.0 - bringing the language features and tooling enhancement from the 7.0.400 SDKs to Ionide.
A massive enhancement to the test explorer integration was contributed by @farlee2121! Thank you! This new version uses the dotnet test listing as the source of truth, and allows go-to-definition.
Update vscode-helpers to have better termination on all platforms.