Support `containers` version `0.8`.

[jonathanknowles]

Upstream issues:

• Support containers version 0.8. basvandijk/scientific#103
• Support containers version 0.8. ekmett/semigroupoids#140
• Support containers version 0.8. fumieval/witherable#105
• Support containers version 0.8. haskell-unordered-containers/hashable#319
• Support containers version 0.8. haskell/aeson#1131
• Support containers version 0.8. haskellari/indexed-traversable#47
• Support containers version 0.8 (in semialign). haskellari/these#207