[2.12] feat: add IsReleaseExists to check if a releaseName already exists or not and GetAppVersion to check the APP VERSION#487

williamshen9999 wants to merge 1 commit intorancher:release/v2.12rancher/shepherd:release/v2.12from

williamshen9999:release/v2.12williamshen9999/shepherd:release/v2.12Copy head branch name to clipboard