web: drop Datadog RUM support
Created by: valerybugakov
Context
Reversal of the https://github.com/sourcegraph/sourcegraph/pull/34063/files since we won't be using Datadog RUM for client observability.
Test plan
n/a — ensure that CI is green.
Created by: valerybugakov
Reversal of the https://github.com/sourcegraph/sourcegraph/pull/34063/files since we won't be using Datadog RUM for client observability.
n/a — ensure that CI is green.