Datadog: upgrade DataDog Agent to 12.6.5301 aka 5.30.1

[olleolleolle]

This PR updates the Agent to the latest 5.x release.

No other changes have been done to the Catalog entry.

Questions for reviewer

• Are there any new features which could be surfaced with the new version?

Features to surface

• [x] proxy_user, proxy_password

[olleolleolle]

Ah, perhaps I ought to NOT upgrade too far.

https://github.com/DataDog/docker-dd-agent/compare/11.0.5140..11.0.5160 this is a better step to begin with.