Update repo labels

Update the repo labels to follow our [convention](https://github.com/GSA/code-gov/blob/master/repository_management.md#labels). 

A [json file](https://github.com/GSA/code-gov/blob/master/repo-labels.json) of the labels we use on code.gov can be use to help with this update. It can be used in conjunction with git-label-cli to do a bulk addition of these labels .