message: create-app: update available package versions to use new core packages
diff: @@ -35,7 +35,9 @@ import { version as catalogClient } from '../../../catalog-client/package.json';
  import { version as catalogModel } from '../../../catalog-model/package.json';
  import { version as cli } from '../../../cli/package.json';
  import { version as config } from '../../../config/package.json';
  -import { version as core } from '../../../core/package.json';
  +import { version as coreAppApi } from '../../../core-app-api/package.json';
  +import { version as coreComponents } from '../../../core-components/package.json';
  +import { version as corePluginApi } from '../../../core-plugin-api/package.json';
  import { version as errors } from '../../../errors/package.json';
  import { version as integrationReact } from '../../../integration-react/package.json';
  import { version as testUtils } from '../../../test-utils/package.json';
  @@ -71,7 +73,9 @@ export const packageVersions = {
  '@backstage/catalog-model': catalogModel,
  '@backstage/cli': cli,
  '@backstage/config': config,
  - '@backstage/core': core,
  + '@backstage/core-app-api': coreAppApi,
  + '@backstage/core-components': coreComponents,
  + '@backstage/core-plugin-api': corePluginApi,
  '@backstage/errors': errors,
  '@backstage/integration-react': integrationReact,
  '@backstage/plugin-api-docs': pluginApiDocs,
  