Report git errors back to the PR comments

[nerdalert]

• Moved git operations into a single method so the error reporting can get wrapped up in a single call. Also pruning down processjob.
• Fixed a bug where if a job failed, job duration being nil would break the iteration.

[nerdalert]

Example output of deleting the tax repo on a worker:

[vishnoianil]

@nerdalert Looks good to me.

I was experimenting with the "Checks" given that we probably need to dump longer text as a result of the command (success, failure). I am on boundary for dumping the error messages in the comment, because once the command is successul, that error message will be still in the comments and that might confuse users (but it probably just me thinking too much 😄 ).

Look at this test PR https://github.com/vishnoianil/taxonomy/pull/21

I added a big bold text in the welcome message itself, saying results/errors of these command will be in the pr status boxes. And you can see three states of these checks (pass, in_progress, failed). If you click the "Details" of each check, you will see the same relevant details as we were dumping in the comments. Let me know what you think?

[nerdalert]

@vishnoianil I like it, the detail click is 💥! Want to merge this and #210 and then push yours and I'll merge it? We should be good to update the deployment Monday/Tues and get feedback. Only comment I want still would be the acknowledgment of the job and a notification of the JobType and JobID for correlation I screencaped in 210. Im gonna get the pretty print tonight. Ty!