rm2

This repository is based off of the past 2 weeks of the homeworks from last week and builds upon the same topics.
Compared to last week with just setting up the repository, I've updated repo_miner.py to have a new fetch_issues method based on the file we were given for our homework. This method will create a dataframe of issues that are not PRs from a given repository. The result of this method running is in issues.csv.
In addition with the repo_miner.py file, I also updated test_repo.py to include 3 new tests. These tests will access the validity of fetch_issues() by testing if the duration days are accurate, confirming that PRs are not included, and that the date is parsed and ISO correctly.