Projects::IssuesController#index frequently times out after 60 seconds

Spun out of https://gitlab.com/gitlab-com/gl-infra/infrastructure/-/issues/9795

We see a fairly consistent 60s timeout failure on Projects::IssuesController#index on GitLab.com, particularly for this URL: https://gitlab.com/gitlab-org/gitlab-foss/issues

This in turn, leads to slow-burn error and apdex alerts on our canary web cluster.

ELK search: https://log.gprd.gitlab.net/goto/d0692baa8e069204a724f4f7212c18fd