Redefine does not work on default type class methods

[lastland]

To fix this, one needs to change the following part:

hs-to-coq/src/lib/HsToCoq/ConvertHaskell/Declarations/Instances.hs

Lines 292 to 302 in 0561cb4

	(Nothing, Nothing, Just term) ->
	let extraSubst
	| meth `elem` classTypes =
	let names = foldMap (^..binderIdents) . filter ((== Explicit) . view binderExplicitness)
	in M.fromList $ zip (names classArgs) [instTy]
	| otherwise =
	mempty
	in -- In the body of the default definition, make methods names
	-- refer to their local version
	-- TODO: Associated type defaults should remember that they're types
	pure . CM_Defined CL_Term $ subst (allLocalNames <> extraSubst) term

to make it recognize edits.