Revert "ci: attempt to reduce flakiness by reducing topgun to 4 nodes"
Revert "ci: attempt to reduce flakiness by reducing topgun to 4 nodes"

still fails with 4 nodes, let's go back to 8

This reverts commit 71ee78fecc27d3d525d14ee4082b70cb04d5a21f.

concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse