Select bounty/project type

**User Story:**
As a funder
I want to be able to have clear bounty types
So that it can meet the needs of if i want one or many contributors submitting work

**Acceptance Criteria**

**Form Initiation**
GIVEN I am creating a bounty
WHEN I navigate to the additional information step
THEN i will have the following two bounty types to choose from:
- Traditional
- Multiple - only available to pro members
AND i will only be able to select one bounty type

**Product & Design Links:**
https://www.figma.com/file/8AFLrc4dx9xnMXUkWOAaAR/Existing-Bounties-Updates?node-id=33%3A1854

**Open Questions:**
- do we need to update any of the functionality of the bounty types? Or is this a simple removal of cooperative and renaming competition to multiple?
**Notes/Assumptions:**