GROOVY-5886 Added ObservableSet plus testcase
Fix typos List -> Set
Merge branch 'master' of https://github.com/groovy/groovy-core
GROOVY-5074 Do not use ExecutorService to run code outside EDT, spawn a new Thread instead
Merge branch 'master' of https://github.com/groovy/groovy-core
Merge branch 'master' of https://github.com/groovy/groovy-core
Merge branch 'master' of https://github.com/groovy/groovy-core