automation: Update penpot Docker tags to v1.11.1

This MR contains the following updates:

Package	Update	Change
penpot-backend_image	patch	1.11.0-beta -> 1.11.1-beta
penpot-exporter_image	minor	1.10.4-beta -> 1.11.1-beta
penpot-frontend_image	patch	1.11.0-beta -> 1.11.1-beta

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