Logs a 'captcha.display' event when a captcha is displayed,
either via web or in an API response, and 'captcha.submit' when
a captcha response is evaluated.
Bug: T91701
Change-Id: I376fdd6740aca4f11776e1326ff2e7e6e5af6a75
Log exceeding the badcaptcha rate limit to the main captcha log (e.g.,
captcha.log on the WMF cluster).
So that we can measure the impact of things like
https://gerrit.wikimedia.org/r/#/c/195886/
Change-Id: I2af26d23b9343e90db2f01f099c1292914bd7ac3