Title: #1134: [Backport][ipa-4-6] Remove the `message` attribute from exceptions
This PR was opened automatically because PR #1121 was pushed to master and backport to
ipa-4-6 is required.
To pull the PR as Git branch:
git remote add ghfreeipa https://github.com/freeipa/freeipa
git fetch ghfreeipa pull/1134/head:pr1134
git checkout pr1134