Bump pillow from 5.1.0 to 8.1.1 in /backend#21

dependabot[bot] wants to merge 1 commit intomasterpradumangoyal/stream:masterfrom

dependabot/pip/backend/pillow-8.1.1pradumangoyal/stream:dependabot/pip/backend/pillow-8.1.1Copy head branch name to clipboard