Make test explorer work with fsac tests and fix an expecto test detection

[TheAngryByrd]

WHAT

🤖 Generated by Copilot at 841c093

This pull request improves the test suite for the LSP features of FsAutoComplete by fixing a build error, reformatting a test file, and enhancing the test setup and runner functions. It also updates the paket.dependencies file and removes a redundant call to dotnetRestore in one of the test files.

🤖 Generated by Copilot at 841c093

To fix a build error they faced They updated YoloDev.Expecto.TestSdk They also improved the test setup and run With DirectoryInfo and -v d for fun And reformatted EmptyFileTests.fs for heck

📦🛠️🧹

WHY

Project work to make Test Run Debugger usable in FSAC.

https://github.com/fsharp/FsAutoComplete/assets/1490044/e200ae68-8d22-435f-bad9-acc27286bb02

HOW

🤖 Generated by Copilot at 841c093

• Fixed a build error by pinning the version of YoloDev.Expecto.TestSdk to 0.14.2 in paket.dependencies (link)
• Simplified the test runner configuration by using the runTestsWithCLIArgsAndCancel function in Program.fs (link)
• Improved the test setup reliability and debugging by using the DirectoryInfo type and the -v d option for the dotnet restore command in Helpers.fs (link)
• Removed unnecessary and redundant calls to dotnetRestore in Server.Tests.fs (link)
• Reformatted EmptyFileTests.fs to use the <| operator and remove extra blank lines for readability and consistency (link, link, link, link)

[TheAngryByrd]

Tangent: I've noticed mac builds failing on so many repositories, makes me think they're busted for dotnet right now.