Resolve "upgrade frost postgres connections to verify-full"

Closes #116 (closed)

Why?

verify-full is currently not working for frost postgresql connections.

by copying the ca-certificates.crt into /home/tomcat/.postgresql/root.crt, tomcat can find the certificate without needing to define the sslrootcert path in the postgresql connection URL

How to test?

• connect to VPN
• fire docker compose up locally
• copy the contents of a tomcat context file from stage (data/tomcat/context/...)
• include sslmode=verify-full in the postgresql url (<Resource ... url=...?sslmode=verify-full)
• wait for frost server to start up (url depends on the name of the context file)
• select e.g. Things to check whether a db connection can be established
  • an empty array shows that the database connection works. if it doesn't, then frost will return an error value

If this MR is merged we can upgrade the frost connections in the context files created by the dispatcher to verify-full.