Because the ovnk build has started taking much longer (graph here), when we have
to build it before running e2e we had to increase the default timeout from 4h0m to
6h0m in order to more easily know if the actual e2e tests are passing. The timeouts
were typically happening in steps after e2e has finished but when it happens the
job is reported as failed.

Once we fully understand the reasons why the build is taking longer we should
revert the change that increased the timeout. It's possible that the build time
is expected for whatever reason and in that case we can close this ticket with that
info.