When encountering an unsupported GHC version, HLS should output the last supported GHC version

[niekvandepas]

Is your enhancement request related to a problem? Please describe.

I just tried using HLS in VS Code (via the Haskell extension) and got an error message saying, "ERROR Error: HLS does not support GHC 9.10.2 yet." Understandable, but it would be nice to know what version of GHC I can use.

Describe the solution you'd like

The error message should include the latest supported GHC version.

Describe alternatives you've considered

Googling it which is annoying and not straightforward, since support for particular GHC versions depends on the version of HLS you're using, which you then have to look up as well, so you have to google how to do that, etc.