SONAR-10696 Remove ability to upgrade/downgrade an edition from Marketplace (#269)

* SONAR-10699 Remove upgrade/downgrade buttons
* SONAR-10697 Drop edition.json support in the marketplace
* SONAR-10717 Drop 'sonar.editions.jsonUrl' property
* SONAR-10702 Edition's "Learn more" links redirect to the form page with arguments
* SONAR-10698 Get Edition data from the doc
* SONAR-10700 Remove LicenseEditionForm and LicenseEditionSet from Marketplace