Add `isSubsequenceOf` to Data.List (#9767)

Niklas Hambüchen suggested that we add the dual of `subsequences`,
isSubsequenceOf (like `isPrefixOf` to `inits` & `isSuffixOf` to `tails`).
It was a simple and noncontroversial proposal which passed unanimously.

For more details see the original proposal discussion at
https://www.haskell.org/pipermail/libraries/2014-November/024063.html

Differential Revision: https://phabricator.haskell.org/D435

Signed-off-by: Alexander Berntsen <alexander@plaimi.net>