(MODULES-905) Extend spec tests for bool2str
(MODULES-905) Extend spec tests for bool2str

The extended spec tests validate that the common types of values
that could be passed to bool2str() are rejected.

fuel-infra/puppetlabs-stdlib,jbondpdx/puppetlabs-stdlib,HelenCampbell/puppetlabs-stdlib,puppetlabs/puppetlabs-stdlib,yadavnikhil/puppetlabs-stdlib,DavidS/puppetlabs-stdlib