Document upload through REST API

[jrcastro2]

• Document how to upload a new video and how to publish it using the REST API.
• Use Bruno for exporting a collection with the example of this workflow.

[zubeydecivelek]

https://codimd.web.cern.ch/Fylk_0SVQl-Z9EEj5eG7AA?view

[ptamarit]

• ✅ The variable baseURl has a weird casing. It should have either a lowercase r or an uppercase L.
  -> changed to uppercase L.
• ✅ Should "Get project to check the flow is finished" be numbered "Step 5" and all the rest be shifted?
• ✅ Should "Optional: Update the Access of the Video" be numbered "Step ..."?
  -> Agreed it doesn't need to be a step.
• ✅ I feel like there is a big redundancy between the CodiMD file and the Bruno collection (URL, headers, params). If the final files are not next to each other in the same repo, they risk getting out of sync.
  -> Bruno cannot generate documentation yet, so we need to maintain both a documentation and the Bruno project.
• It might be worth getting a review from a Bruno expert (Carlin, Alex, Nico).

[zubeydecivelek]

Same content also added to CDS Videos README file