Introduce configuration properties prefix constants for OAuth2ResourceServerProperties

[quaff]

There are too many hard-coded spring.security.oauth2.resourceserver.* in the codebase, it's better to introduce constants like:

@ConfigurationProperties(OAuth2ResourceServerProperties.PROPERTIES_PREFIX)
public class OAuth2ResourceServerProperties {

	public static final String PROPERTIES_PREFIX = "spring.security.oauth2.resourceserver";

	public static final String JWT_PROPERTIES_PREFIX = PROPERTIES_PREFIX + ".jwt";

	public static final String OPAQUETOKEN_PROPERTIES_PREFIX = PROPERTIES_PREFIX + ".opaquetoken";

Feel free to close it or assign it to me.

[philwebb]

I'm always a little torn with things like this. A constant is nice if we ever want to change the prefix, but I find things generally harder to read with the extra layer of indirection and often just prefer the duplication.

[wilkinsona]

The constants also don't protect against bugs like #46627 as you could still use the wrong one so I'm not sure there's that much benefit. I think I prefer the duplication too.

[nosan]

Personally, I always struggle to read code when I see many constants prefixed like this. It is better to duplicate them and cover them with unit tests.

[philwebb]

Thanks both. I think in this case we'll stick to the way things are.