feat: update rate limit logic

[alexey-yarmosh]

Fixes #364

Scenario:

• user has 100 credits
• user does a request with "limit": 200
• user gets a 429 http error. Number of user credits is unchanged
• user does a request with "limit": 100
• user gets a valid 202 http response. Number of user credits is updated to 0 (or to a bigger number if "probesCount" in the response is less than 100).