enable hlsCheck

[peterbecich]

https://srid.ca/haskell-template/checks

---

I wonder if related to #1250

l/Email.hs
Hidden:   no
Range:    1:1-2:1
Source:   cradle
Severity: DiagnosticSeverity_Error
Message: 
  Error when calling cabal exec -v0 -- ghc --print-libdir

  dieVerbatim: user error (Error: cabal: Couldn't establish HTTP connection. Possible cause: HTTP
  proxy
  server is down.
  )

[peterbecich]

This is probably blocked by the sandbox: srid/haskell-flake#21