Issue #3426309 by Wim Leers, smustgrave: Add config validation for weights (blocks, filters, etc. all use weights)

Issue #3332593 by phenaproxima, Wim Leers, borisson_, lauriii, tim.plunkett: Adopt PluginExists validator in relevant places

Issue #3341682 by Wim Leers, phenaproxima, borisson_, catch, alexpott: New config schema data type: required_label

Issue #2920678 by phenaproxima, Wim Leers, dawehner, Gogowitsch, Sam152, dww, longwave, yogeshmpawar, alexpott, borisson_, tstoeckler, jibran, amateescu, larowlan, tedbow: Add config validation for the allowed characters of machine names

Issue #2849827 by Sam152, timmillwood, larowlan: Move workflow "settings" setters and getters to WorkflowTypeInterface

Issue #2779647 by alexpott, Sam152, catch, scookie, yoroy, pericxc, timmillwood, tacituseu, jhedstrom, xjm, bojanz, tstoeckler: Add a workflow component, ui module, and implement it in content moderation