ci: add e2e tests

PR pending waiting for !30 (merged)

This MR implements e2e pipeline which does the following:

• installs deps (playwright)
• downloads 1um (1255) from ebrains and spins up tiamat-ng
• downloads & serves vanilla neuroglancer viewer
• use playwright to open the tiamat-ng served 1um on neuroglancer viewer, recording the video and upload as artefact

CI in action: https://jugit.fz-juelich.de/inm-1/bda/software/data_access/tiamat/tiamat-ng/-/jobs/1090734