Address CVEs related to Calamares and insecure handling of files and permissions when using Full Disk Encryption.
CVEs:
CVE-2019-13178
https://github.com/calamares/calamares/issues/1190
https://bugs.launchpad.net/ubuntu/+source/calamares/+bug/1835095
CVE-2019-13179
https://github.com/calamares/calamares/issues/1191
https://bugs.launchpad.net/ubuntu/+source/calamares/+bug/1835095