adapt to changes in unliftio-core-0.2.0.1

[alanz]

In particular

fpco/unliftio@d327ae4

Which results in

Haskell/Ide/Engine/PluginsIdeMonads.hs:588:16: error:
    The INLINE pragma for ‘askUnliftIO’ lacks an accompanying binding
      (The INLINE pragma must be given where ‘askUnliftIO’ is declared)
    |
588 |     {-# INLINE askUnliftIO #-}
    |                ^^^^^^^^^^^

Haskell/Ide/Engine/PluginsIdeMonads.hs:589:5: error:
    ‘askUnliftIO’ is not a (visible) method of class ‘MonadUnliftIO’
    |
589 |     askUnliftIO = Ghc $ \s ->
    |     ^^^^^^^^^^^

Haskell/Ide/Engine/PluginsIdeMonads.hs:600:16: error:
    The INLINE pragma for ‘askUnliftIO’ lacks an accompanying binding
      (The INLINE pragma must be given where ‘askUnliftIO’ is declared)
    |
600 |     {-# INLINE askUnliftIO #-}
    |                ^^^^^^^^^^^

Haskell/Ide/Engine/PluginsIdeMonads.hs:601:5: error:
    ‘askUnliftIO’ is not a (visible) method of class ‘MonadUnliftIO’
    |
601 |     askUnliftIO = GhcT $ \s ->
    |     ^^^^^^^^^^^

[jneira]

To temporary allow update the cabal index state i've added to cabal projects:

constraints:
        -- to avoid temporary a breaking change: https://github.com/haskell/haskell-ide-engine/issues/1680
        unliftio-core < 0.2.0.0,

We should remove it when the code compiles with the new version