api: Implement progressive catalysis

[victorges]

What does this pull request do? Explain your changes. (required)

This is to allow migrating only partially to the new Catalyst pipeline, by providing a "gradual rollout percent"
flag on the command line used when creating new assets to randomly select a % of assets to go through
the new flow.

Specific updates (required)

• Create the flag
• Use it
• Update the API schema to add upload task type officially

-

• How did you test each of these updates (required)
  yarn test

Does this pull request close any open issues?
Implements #1269

Checklist:

• I have read the CONTRIBUTING document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.

[vercel]

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livepeer-studio	✅ Ready (Inspect)	Visit Preview	Sep 20, 2022 at 7:27PM (UTC)

[codecov]

Codecov Report

Merging #1273 (57d8521) into master (24f512e) will increase coverage by 0.02369%.
The diff coverage is 33.33333%.

@@                 Coverage Diff                 @@
##              master       #1273         +/-   ##
===================================================
+ Coverage   51.28146%   51.30515%   +0.02368%     
===================================================
  Files             66          66                 
  Lines           4331        4329          -2     
  Branches         802         803          +1     
===================================================
  Hits            2221        2221                 
+ Misses          1829        1826          -3     
- Partials         281         282          +1     

Impacted Files	Coverage Δ
packages/api/src/parse-cli.ts	31.70732% <ø> (ø)
packages/api/src/controllers/asset.ts	55.13699% <33.33333%> (+0.37509%)	⬆️

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Impacted Files	Coverage Δ
packages/api/src/parse-cli.ts	31.70732% <ø> (ø)
packages/api/src/controllers/asset.ts	55.13699% <33.33333%> (+0.37509%)	⬆️

[gioelecerati]

LGTM