Enable passing the certificate authority on the relation in order to
enable TLS communication to the MySQL DB.
In order to enable MySQL to use TLS for client connections all that
is required is the CA certificate. A certificate and key may be used
for client certificate authentication. However, since almost all
deployments will not use certificate authentication, focusing on the CA as SSL
data complete makes sense.
Change-Id: I785afe7f64cb57caa857178d529e3cabdcf63517
Prior to this change there was no way to specify a port for mysql
connections. Add this to the Shared DB connection information.
Change-Id: Iafcc106fca44479e89b4b66a0a3988ffeee01f04
Closes-Bug: #1876188