ci : add action for finding duplicate issues (#20756)
* ci : add action for finding duplicates issues
* cont : gen info
* cont : formatting
* cont : fix
* cont : instructions
* cont : bump checkout action
Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
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Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
