Wait for circle to lighthouse

[bollwyvl]

Sorry #208 wasn't right the first time: i don't have any circle stuff set up.

This PR tests the hypothesis that the circle site is not quite fully baked by the time lighthouse gets to it... it's a little hard to tell without some tighter timings. Anyhow, this will wait up to a minute with curl until a "good" result comes back

It also turns on the lighthouse verbose setting.

[jorisvandenbossche]

OK, let's see how that goes .. (it's a bit annoying that we can't test this on a PR, since the status check uses the code in master, as I understand?)

[jorisvandenbossche]

Hmm, no luck: still timing out: https://github.com/pandas-dev/pydata-sphinx-theme/runs/799323015?check_suite_focus=true