When you SELECT a boolean from system.config, it reads as true/false, but this isn't accepted
on UPDATE (instead, we accept 1/0). This is surprising and annoying, so accept true/false in
both directions.
Not a regression, so a backport isn't strictly necessary.
Closesscylladb/scylladb#19792
* github.com:scylladb/scylladb:
config: specialize from-string conversion for bool
config: wrap boost::lexical_cast<> when converting from strings
9eb47b3ef0