Allow to pass bindist configure arguments

@bgamari requested

Relevant code:

• https://gitlab.haskell.org/haskell/ghcup-hs/-/blob/master/app/ghcup/GHCup/OptParse/Install.hs
• https://gitlab.haskell.org/haskell/ghcup-hs/-/blob/master/lib/GHCup/GHC.hs#L122

changed milestone to %0.1.18.0

added typeimprovement label

mentioned in commit 4022edb1

mentioned in merge request !262 (merged)

mered in !262 (merged)

closed

Thanks, @maerwald! For the record, this came up in the context of ghc/ghc#21570 (closed) (which is at its core a GHC bug).