Trino Gateway should support http-client configurations specific to authentication modules (e.g. OAuth2)

[AndyJiang99]

Similar to how in Trino, HTTP client properties can be specified to enable HTTP client properties for authentication HTTP interactions, Trino Gateway should also support this functionality to enable proxying for different authentications.

The following properties can be used after adding the specific prefix to the property. For example, for [OAuth 2.0 authentication](https://trino.io/docs/current/security/oauth2.html), you can enable HTTP for interactions with the external OAuth 2.0 provider by adding the prefix oauth2-jwk to the http-client.connect-timeout property, and increasing the connection timeout to ten seconds by setting the value to 10:

oauth2-jwk.http-client.connect-timeout=10s
The following prefixes are supported:

oauth2-jwk for [OAuth 2.0 authentication](https://trino.io/docs/current/security/oauth2.html)

jwk for [JWT authentication](https://trino.io/docs/current/security/jwt.html)

exchange to configure data transfer between Trino nodes in addition to [Exchange properties](https://trino.io/docs/current/admin/properties-exchange.html)

from https://trino.io/docs/current/admin/properties-http-client.html

[xkrogen]

A few other issues that may be related:
#631
#449
#616

One issue here is that Gateway currently doesn't use Airlift's configuration management framework, so we can't just leverage the Airlift properties as drop-in replacement. See some discussions:
#378
#554

@mosabua @oneonestar if you know -- did we have alignment on maintaining a custom config approach (nested YAML) indefinitely in GW vs eventually aligning to use Airlift Configuration?

[mosabua]

We are supporting airlift configurations with the yaml config. At some stage it would be nice to expand airlift to support yaml or toml or some other format that allows nesting but for now we are just supporting airlift config in the separate sections.

The plumbing is essentially there.. for wider support we need to switch any HTTP client in use to the airlift one and then wire it up for config just like it is done in Trino.. feel free to send PRs for whatever HTTP client use you want to implement this for..