Revert "Experimental reference panel: add independent pagination for references/implementations (#31403)"

Created by: mrnugget

This reverts commit d53f2298d1fb9d05444ed8a026da75032f441944.

Test plan

• E2E tests fail: https://buildkite.com/sourcegraph/sourcegraph/builds/133049#d7408ec2-3cf0-42fb-b5d6-8733ddcf7a7f