master: update test for config default

Commit 1aec747c10f0d5077842294ca351b918b77fb1e9 added a
default for graph_strategy. test has be updated.
node: use a 5% tolerance for timings tests

If the tests are done on a VM, the timings are not precise enough. So increase the error margin to cope with it.

It was at 0.5%, and this commits sets it at 5%