Open Third-Party Licenses update pull request

When releasing a Nuxeo Server version, we want to open a pull request on the documentation with all the third-party dependencies license up to date based on the promoted version.

This means automatically update the table found in the page https://doc.nuxeo.com/nxdoc/next/licenses/

The following script is used to generate a markdown table of all third-party dependencies: https://github.com/nuxeo/nuxeo/blob/master/scripts/generate-licenses.py

Add a new pipeline job generating the markdown table and creating the pull request.