[tune](deps): Bump pytorch-lightning from 1.0.3 to 1.2.8 in /python/requirements#16

dependabot[bot] wants to merge 1 commit intomasterijrsvt/ray:masterfrom

dependabot/pip/python/requirements/pytorch-lightning-1.2.8ijrsvt/ray:dependabot/pip/python/requirements/pytorch-lightning-1.2.8Copy head branch name to clipboard