Found at least one missing field type validation that's causing problems with one of our packages.

appears to be missing boolean validation logic, so we're missing test cases such as this where a string "yes" isn't being properly mapped to a boolean value at ingest and is causing our package to be broken.

I think, at minimum, we should probably audit all of the Elasticsearch types we're likely to be using and make sure they're supported in our validation routines.

cc: @elastic/security-external-integrations