Doc improve section about active profiles programmatic access

[Postremus]

Description

I wanted to activate a feature in my app only when dev mode is active.
The class is not a cdi bean (OASFilter), so IfBuildProfile does not help me.

I did not quite remember the manual way to check profiles, and tried to look it up in the doc.
ConfigProvider.getConfig().unwrap(SmallRyeConfig.class).getProfiles() states to use io.smallrye.config.SmallRyeConfig#getProfiles to retrieve the currently active profiles.

However, that is a bit confusing imo. SmallRyeConfig#getProfiles is not a static method, and therer is no doc on that class on how to obtain an instance.

After a bit of searching I found ConfigUtils.getProfiles() which does a simple unwrap / cast.
ConfigProvider.getConfig().unwrap(SmallRyeConfig.class).

The doc could be a bit more clearer on how to get the active profiles.

Implementation ideas

No response

[quarkus-bot]

/cc @radcortez (config)