chore(sdk): Cherry pick kubeflow#6844 and kubeflow#6851 to sdk/releas…

…e-1.8 branch (kubeflow#6852)

* fix(sdk): fix cloud scheduler's job name (kubeflow#6844)

* chore(sdk): add deprecation warnings for v2 (kubeflow#6851)

* chore(sdk): Release 1.8.8 off `sdk/release-1.8` branch (kubeflow#6853)

Co-authored-by: Trs <trsnium@gmail.com>
Co-authored-by: Yaqi Ji <jiyaqi0712@gmail.com>