Rate limit is applied even if login/registration failed

[Nutomic]

Login and registration have a very low rate limit of 3 requests per hour. This can easily be hit by mistyping the login password three times in a row, or putting the wrong captcha on registration. Afterwards you only see ratelimit errors. To resolve this the rate limit should only be applied if the action was successful.

Also login is a relatively cheap action and can use a higher limit.

[dessalines]

We've had this issue before, and I thought we fixed it. It might just be easier to up that rate limit.

[Nutomic]

Its not handled in the code, and would be tricky to add. Hopefully it can be done as part of #5550. Agree about increasing the rate limit especially for 0.19