Add source jars for all artifacts

[philwebb]

           properties: [
            { name: 'typeId', value: 'sources-staging' },
            {
              name: 'failureMessage',
              value: "Missing: no sources jar found in folder '/io/spring/javaformat/***.javaformat.eclipse.tests/0.0.42'"
            },
            {
              name: 'failureMessage',
              value: "Missing: no sources jar found in folder '/io/spring/javaformat/***.javaformat.eclipse/0.0.42'"
            }
          ]