Adding Labels To Pulls

## Description and Impact
> What impact does this change have for production?

## Deploy Plan
> Does Infrastructure need to know anything special about this deploy?

## Rollback Plan
* To roll back this change, revert the merge with: `git revert -m 1 MERGE_SHA` and perform another deploy.

## URLs
> Links to bug tickets or user stories.

## QA Plan
> Fill in scenarios below. Review [QA Best Practices](https://source.sportngin.com/page/show/1227795-qa-best-practices).

#### Risk Level:
- [ ] Low
- [ ] Medium
- [ ] High

#### Happy Path Scenarios
* Happy Path scenario 1
* Happy Path scenario 2

#### Additional Scenarios (Edge Case, Negative, etc.)
* Edge case scenario 1
* Edge case scenario 2

#### Regression Scenarios
* Regression item on related feature 1
* Regression item on related feature 2

they show up in the labels_pull_requests table...