Add live stream policy

[setmao]

Types of changes

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• [ ] Bugfix
• [x] New feature
• [ ] Refactoring
• [ ] Breaking change (any change that would cause existing functionality to not work as expected)
• [ ] Documentation Update
• [ ] Other (please describe)

Description

Describe what the change is Add "Live stream policy" select in proposals create/update page.

Steps to Test This Pull Request

Steps to reproduce the behavior:

1. Go to "MY PYCONTW".
2. Click on "Create New Talk Proposal (投稿新演講)" or "Create New Tutorial Proposal (投稿新專業課程)".
3. When "recording policy's(議程錄影)" value is False.

Expected behavior

Should see "Live stream policy (議程直播)" select is below "recording policy (議程錄影)" select.

More Information

Screenshots

[mattwang44]

oops it seems the CI failed. Can you also fix the test cases?