Hackathon Bounties show on explorer prior to start date

**Steps To Reproduce**
Steps to reproduce the behavior:
1. Set up a hackathon
2. Set start date for hackathon for in the future
3. Create a bounty tied to that hackathon
4. View normal bounty explorer on a date prior to the start date of hackathon

**Observed behavior**
Bounty that was created displays on the issue explorer to all contributors

**Expected behavior**
Bounties shouldnt show on the bounty explorer until the start date and time has passed. Should be the same behavior that works currently on the prize explorer for a hackathon