A note on CONTRIBUTING.md lint barrier, its removal through automation

[Anton-Latukha]

Describe what you were trying to get done.

Notifying that after: haskell/actions#85 & haskell/actions#86 are done the:

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Can be fully lifted away, since it would not be needed from contributors as that CI barriers would be solved & replaced by a humanitarian approach.

The project would be able to move to workflow described here: ndmitchell/hlint#1311 (comment).

In several words - proper action gives a soft way of annotating the pull request code (a soft-mode which many GitHub users not experienced currently) changes & so would softly to both sides just show what hlint is suggesting on the commit diffs. Because of that, the contributors by themselves would be encouraged.