docs: added DB_SSL and DB_SSL_CA to helm chart (#2492)

***NO_CI***

* Update deployment.yaml

added DB_SSL option for postgres

* Update README.md

added note about `postgresql.ssl`

* added DB_SSL_CA

* added postgressql.ca note

* Update values.yaml

added more PostgresSQL details to values.yml

* Update values.yaml

* Update values.yaml

removed whitespace

* Update README.md

added ssl and ca notes

* Update README.md

* Update README.md

* Update README.md

* Update README.md

* Update README.md

* docs: update README

Co-authored-by: Nicolas Giard <github@ngpixel.com>