NFTokenAcceptOffer wrong buyer in broker mode

[shawnxie999]

High Level Overview of Change

Context of Change

In brokered mode, the buyer inside simple view for NFTokenAcceptOffer is incorrect due to 2 NFTokenOffer nodes

• We can get the seller and buy by checking if the Flags field is 1 or 0 respectively

Type of Change

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] Refactor (non-breaking change that only restructures code)
• [x] Tests (You added tests for code that already exists, or your new feature included in this PR)
• [ ] Documentation Updates
• [ ] Release

TypeScript/Hooks Update

• [ ] Updated files to React Hooks
• [ ] Updated files to TypeScript

Before / After

Before

After

Test Plan