Add support for custom tls config in Vertica driver

[vilderxyz]

Vertica driver supports custom TLS configuration, but the path to the custom CA needs to be passed somehow. I was considering adding it as a variable or as a connection string query. Finally, I found that passing it in queries was sufficient for me. This approach has worked for me, so I have decided to create a pull request and share my small changes.

Let me know how you feel about it. I am open to discussion and ready to make adjustments to ensure that these changes align with your requirements.

With this change, an example connection string with path to custom CA would look like this - vertica://user:password@host:port/database?tlsmode=/path/to/ca

12.06.2023:

• with those changes, secure connection with custom TLS config can be established via vertica://<user>:<password>@<host>:<port>/<database>?tlsmode=server-strict&ca_path=/path/to/ca, where ca_path is one of custom config. The solution allows to support more of TLS options in the connection's string query if added to customTlsConfig map.

[vodrazka]

hi @nineinchnick, do you know when this could be merged and released?

[nineinchnick]

Sorry, I forgot about it. LGTM, thank you for the contribution and your patience!