feat: Add is_live and is_upcoming to VideoDetails

[absidue]

Description

The current is_live_content property only tells you whether the video is a normal one or a live stream, it doesn't provide enough granularity on whether the live stream is live, upcoming or a live stream replay, it's true for all three of those. Extracting the is_live and is_upcoming properties as well, solves that.

Below is a table of the values of those 3 properties for the 4 types of videos mentioned above.

Type	is_live	is_live_content	is_upcoming
currently live live stream	true	true	false
live stream replay	false	true	false
upcoming live stream	false	true	true
normal video	false	false	false

I haven't added any tests as it'll be hard to find continously running live streams and upcoming live streams that never actually start.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have checked my code and corrected any misspellings

[ChunkyProgrammer]

I believe this is a continuous livestream:
https://youtu.be/jfKfPfyJRdk

And we used this for a test in yt-channel-info but we might need a better example:
https://youtu.be/O3cCYok_ukk

[absidue]

Added test now.