This is not currently supported.
From a review of the JDBC connection string details, Microsoft has added new parameters to the MS SQL JDBC Driver:
https://docs.microsoft.com/en-us/sql/connect/jdbc/connecting-with-ssl-encryption?view=sql-server-2017
"...new connection string properties such as encrypt, trustServerCertificate, trustStore, trustStorePassword, and hostNameInCertificate, "
We deploy and connect to MS SQL using a 3rd party JDBC Driver from JTDS, which does not support those new connection string parameters:
http://jtds.sourceforge.net/faq.html
We are updating our connection to the MS SQL database in Process Automation release 4.3 sp3, which is due out in June, to use the latest JDBC Driver directly from Microsoft.
I am not finding any details that the installation will support the initial install using SSL, but we are supporting newer SQL features such as the AlwaysOn option, and we may have an option to allow the installer to connect to a Secure only MSSQL database.
I am checking around internally to see if I can locate any more specifics on this.