docs: add missing index entry
docs: add missing index entry for "Slow / failure to boot dind sidecar (default runner)"
* [Runner coming up before network available](#runner-coming-up-before-network-available)
* [Outgoing network action hangs indefinitely](#outgoing-network-action-hangs-indefinitely)
* [Unable to scale to zero with TotalNumberOfQueuedAndInProgressWorkflowRuns](#unable-to-scale-to-zero-with-totalnumberofqueuedandinprogressworkflowruns)
+ * [Slow / failure to boot dind sidecar (default runner)](#slow--failure-to-boot-dind-sidecar-default-runner)
## Tools
