Support `containers` version `0.8`.

[jonathanknowles]

Version 0.8 of the containers package has been released, but witherable currently has an upper bound of < 0.8:

witherable/witherable/witherable.cabal

Lines 27 to 29 in 455a568

	build-depends: base >=4.9 && <5,
	base-orphans >=0.8.4 && <0.10,
	containers >=0.5.7.1 && <0.8,

[mpilgrem]

GHC 9.14.1 comes with containers-0.8. witherable-0.5 builds with GHC 9.14.1.