ASCN-234: Add support for oidc/okta configuration

[stephen-vakil]

This adds support for okta authentication to opserver's charts. This required adding environment variables for the various OIDC/okta settings. In getting this working, I found two issues:

1. When running in a container, the app is hosted over http with https provided via ingress. However, the app, when redirecting to okta, was previously using the same scheme as the Request. As a result, when it was creating the redirectUri for okta, it used http which is not appropriate. I added a shared method and a new setting to handle this -- if the setting is set, it will use https always.
2. The default connection string's database name set up in the chart was Local.Exceptions which is not appropriate outside of local. I am not sure where the default connection string is used, but in the documentation sample they used master as the database for the default connection string, which seems as good as any?

[WouterDeKort]

Overall LGTM. Adding the HTTPS redirect setting/method makes sense to. Left some small comments but nothing major.

[WouterDeKort]

LGTM!