ci/flake: TestStructuralLimits/limited disabled

Created by: jhchabran

Test

TestStructuralLimits/limited

Example failure

https://buildkite.com/sourcegraph/sourcegraph/builds/157566

Disabling PR

https://github.com/sourcegraph/sourcegraph/pull/38025

Additional details

https://sourcegraph.slack.com/archives/C02FLQDD3TQ/p1656605688287039

cc @sourcegraph/search-core