Yes, Crawlera counts redirects as successful requests.
For example: if a user makes a request through Crawlera to http://mysite.com and the response is
302 Found with a location header to follow https://mysite.com, and the crawler follows that link through Crawlera account, it will get accounted for two requests.
Crawlera does not follow redirects by itself, it only executes a single HTTP request, returning its HTTP response. So, if a 3XX response is received, the crawler should decide whether to following it or not.
Note that if you're getting many 3XX redirects, you may be able to optimize your spider code to save Crawlera requests and make the crawl more efficient.