Maybe correction on the Fibonacci Example in IOIntroduction

[hln]

I believe this line https://github.com/rockthejvm/cats-effect/blob/master/src/main/scala/com/rockthejvm/part2effects/IOIntroduction.scala#L108 should read:

if (n <= 2) IO(1)

Otherwise, in the video, it says fibonacci(10) is 89 when it's 55. I would have asked in the Slack channel, but I lost the original email 😭, and also I get a 403 when pushing up a local branch for a pull request.