I am also having the same issue, been looking all over, changing gradle version to match my projects java version, uninstalling gradle, reinstalling. Everything i can think of, still getting the same error:
Plugin [id: 'com.mark.bootstrap.bootstrap', version: '63065322f4', artifact: 'com.github.Mark7625:bootstrap-release:63065322f4'] was not found in any of the following sources: